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ACDelco
2007 Buick Rendezvous Power Brake Booster ACDelco

P311-2DCEBC1    W0133-1684318  New

Qty:
$565.24
  • This Original Equipment Manufacturer part is the same part that was made & installed by the car manufacturer at the factory where the car was produced.
  • GM Original Equipment
  • Front
Brand: ACDelco
Additional Fitment Information:
Vehicle
2007 - Buick Rendezvous
Cardone
2000 Buick Regal Power Brake Booster Cardone - Reman. A-1 CARDONE Vacuum Power Brake Booster w/o Master Cylinder

P311-095E1BD    54-74823  Remanufactured

18042269 , 19121403 , 15236237 , 88967238 , 18048230

Qty:
$25.20 $118.36
Cardone Power Brake Booster
  • Remanufactured Vacuum Power Brake Booster w/o Master Cylinder
  • Reman. A-1 CARDONE Vacuum Power Brake Booster w/o Master Cylinder
  • Product Attributes:
    • Diaphragm Diameter (in): 12.10
    • Diaphragm Diameter (mm): 307.34
    • Features and Benefits:
      • 100% O.e. Quality Seals, Diaphragms And Check Valves Are Installed On Every Unit For Like-new Performance And Reliability
      • All Units Are 100% Tested To Ensure Reliable Performance
      • Exclusive Rust-prohibitive Finishing Process Extends Unit Life
      • Guaranteed Fit And Function
      • Master Cylinder Output Rods Are Pre-adjusted (when Included) For Easier And Faster Installation
      • Meets Or Exceeds O.e.m Performance
      • New Mounting Nuts And Washers Ensure Proper, Hassle-free Installation
    • Master Cylinder Stud Thread Size: M10 X 1.5
    • Product Condition: Remanufactured
  • A1 CARDONE Remanufactured Vacuum Brake Boosters, Hydro-Vac Boosters, and Hydraulic Boosters, offer your vehicle reliable stopping performance, every time. Each unit is reverse engineered, based off 40 years of CARDONE Engineering expertise, where original design weaknesses are identified, corrected and where applicable upgraded to provide a more durable part then the original unit. Every unit is remanufactured to meet or exceed OEM performance, providing a quality product both you and your vehicle rely on.
Brand: Cardone
Additional Fitment Information:
Vehicle
2000 - Buick Regal
Cardone
1998 Buick Regal Power Brake Booster Cardone - Reman. A-1 CARDONE Vacuum Power Brake Booster w/o Master Cylinder

P311-53366D2    54-74825  Remanufactured

18029876

Qty:
$13.50 $71.00
Cardone Power Brake Booster
  • Remanufactured Vacuum Power Brake Booster w/o Master Cylinder
  • Reman. A-1 CARDONE Vacuum Power Brake Booster w/o Master Cylinder
  • Product Attributes:
    • Diaphragm Diameter (in): 12.10
    • Diaphragm Diameter (mm): 307.39
    • Features and Benefits:
      • 100% O.e. Quality Seals, Diaphragms And Check Valves Are Installed On Every Unit For Like-new Performance And Reliability
      • All Units Are 100% Tested To Ensure Reliable Performance
      • Exclusive Rust-prohibitive Finishing Process Extends Unit Life
      • Guaranteed Fit And Function
      • Master Cylinder Output Rods Are Pre-adjusted (when Included) For Easier And Faster Installation
      • Meets Or Exceeds O.e.m Performance
      • New Mounting Nuts And Washers Ensure Proper, Hassle-free Installation
    • Master Cylinder Stud Thread Size: M10 X 1.5
    • Product Condition: Remanufactured
  • A1 CARDONE Remanufactured Vacuum Brake Boosters, Hydro-Vac Boosters, and Hydraulic Boosters, offer your vehicle reliable stopping performance, every time. Each unit is reverse engineered, based off 40 years of CARDONE Engineering expertise, where original design weaknesses are identified, corrected and where applicable upgraded to provide a more durable part then the original unit. Every unit is remanufactured to meet or exceed OEM performance, providing a quality product both you and your vehicle rely on.
Brand: Cardone
Additional Fitment Information:
Vehicle
1998 - Buick Regal
Cardone
Qty:
Cardone Power Brake Booster
  • Remanufactured Vacuum Power Brake Booster w/o Master Cylinder
  • Reman. A-1 CARDONE Vacuum Power Brake Booster w/o Master Cylinder
  • Product Attributes:
    • Diaphragm Diameter (in): 10.450
    • Diaphragm Diameter (mm): 265.430
    • Features and Benefits:
      • 100% O.e. Quality Seals, Diaphragms And Check Valves Are Installed On Every Unit For Like-new Performance And Reliability
      • All Units Are 100% Tested To Ensure Reliable Performance
      • Exclusive Rust-prohibitive Finishing Process Extends Unit Life
      • Guaranteed Fit And Function
      • Master Cylinder Output Rods Are Pre-adjusted (when Included) For Easier And Faster Installation
      • Meets Or Exceeds O.e.m Performance
      • New Mounting Nuts And Washers Ensure Proper, Hassle-free Installation
    • Master Cylinder Stud Thread Size: 3/8 X 16
    • Product Condition: Remanufactured
  • A1 CARDONE Remanufactured Vacuum Brake Boosters, Hydro-Vac Boosters, and Hydraulic Boosters, offer your vehicle reliable stopping performance, every time. Each unit is reverse engineered, based off 40 years of CARDONE Engineering expertise, where original design weaknesses are identified, corrected and where applicable upgraded to provide a more durable part then the original unit. Every unit is remanufactured to meet or exceed OEM performance, providing a quality product both you and your vehicle rely on.
Brand: Cardone
Additional Fitment Information:
Vehicle
1967 - Buick Sportwagon
Cardone
2004 Buick Rainier Power Brake Booster Cardone - Reman. A-1 CARDONE Vacuum Power Brake Booster w/o Master Cylinder

P311-10F7E48    54-74821  Remanufactured

18047694 , 8180476940 , DL178670 , 8180444440 , DELCO178670 , 18044444 , 15247618

Qty:
$17.10 $76.42
Cardone Power Brake Booster
  • Remanufactured Vacuum Power Brake Booster w/o Master Cylinder
  • Reman. A-1 CARDONE Vacuum Power Brake Booster w/o Master Cylinder
  • Product Attributes:
    • Diaphragm Diameter (in): 11.06
    • Diaphragm Diameter (mm): 280.80
    • Features and Benefits:
      • 100% O.e. Quality Seals, Diaphragms And Check Valves Are Installed On Every Unit For Like-new Performance And Reliability
      • All Units Are 100% Tested To Ensure Reliable Performance
      • Exclusive Rust-prohibitive Finishing Process Extends Unit Life
      • Guaranteed Fit And Function
      • Master Cylinder Output Rods Are Pre-adjusted (when Included) For Easier And Faster Installation
      • Meets Or Exceeds O.e.m Performance
      • New Mounting Nuts And Washers Ensure Proper, Hassle-free Installation
    • Master Cylinder Stud Thread Size: M10 X 1.5
    • Product Condition: Remanufactured
  • A1 CARDONE Remanufactured Vacuum Brake Boosters, Hydro-Vac Boosters, and Hydraulic Boosters, offer your vehicle reliable stopping performance, every time. Each unit is reverse engineered, based off 40 years of CARDONE Engineering expertise, where original design weaknesses are identified, corrected and where applicable upgraded to provide a more durable part then the original unit. Every unit is remanufactured to meet or exceed OEM performance, providing a quality product both you and your vehicle rely on.
Brand: Cardone
Additional Fitment Information:
Vehicle
2004 - Buick Rainier
Cardone
2005 Buick Terraza Power Brake Booster Cardone - Reman. A-1 CARDONE Vacuum Power Brake Booster w/o Master Cylinder

P311-259882E    54-74827  Remanufactured

15234621 , 18045787 , 18029880 , 15189237

Qty:
$35.10 $103.27
Cardone Power Brake Booster
  • Remanufactured Vacuum Power Brake Booster w/o Master Cylinder
  • Reman. A-1 CARDONE Vacuum Power Brake Booster w/o Master Cylinder
  • Product Attributes:
    • Diaphragm Diameter (in): 11.06
    • Diaphragm Diameter (mm): 280.80
    • Features and Benefits:
      • 100% O.e. Quality Seals, Diaphragms And Check Valves Are Installed On Every Unit For Like-new Performance And Reliability
      • All Units Are 100% Tested To Ensure Reliable Performance
      • Exclusive Rust-prohibitive Finishing Process Extends Unit Life
      • Guaranteed Fit And Function
      • Master Cylinder Output Rods Are Pre-adjusted (when Included) For Easier And Faster Installation
      • Meets Or Exceeds O.e.m Performance
      • New Mounting Nuts And Washers Ensure Proper, Hassle-free Installation
    • Master Cylinder Stud Thread Size: M10 X 1.5
    • Product Condition: Remanufactured
  • A1 CARDONE Remanufactured Vacuum Brake Boosters, Hydro-Vac Boosters, and Hydraulic Boosters, offer your vehicle reliable stopping performance, every time. Each unit is reverse engineered, based off 40 years of CARDONE Engineering expertise, where original design weaknesses are identified, corrected and where applicable upgraded to provide a more durable part then the original unit. Every unit is remanufactured to meet or exceed OEM performance, providing a quality product both you and your vehicle rely on.
Brand: Cardone
Additional Fitment Information:
Vehicle
2005 - Buick Terraza
Cardone
1987 Buick Somerset Power Brake Booster Cardone - Reman. A-1 CARDONE Vacuum Power Brake Booster w/o Master Cylinder

P311-521BA00    54-71210  Remanufactured

18015980 , 18013875 , 18016702

Qty:
$4.50 $71.00
Cardone Power Brake Booster
  • Remanufactured Vacuum Power Brake Booster w/o Master Cylinder
  • Reman. A-1 CARDONE Vacuum Power Brake Booster w/o Master Cylinder
  • Product Attributes:
    • Diaphragm Diameter (in): 9.12
    • Diaphragm Diameter (mm): 231.52
    • Features and Benefits:
      • 100% O.e. Quality Seals, Diaphragms And Check Valves Are Installed On Every Unit For Like-new Performance And Reliability
      • All Units Are 100% Tested To Ensure Reliable Performance
      • Exclusive Rust-prohibitive Finishing Process Extends Unit Life
      • Guaranteed Fit And Function
      • Master Cylinder Output Rods Are Pre-adjusted (when Included) For Easier And Faster Installation
      • Meets Or Exceeds O.e.m Performance
      • New Mounting Nuts And Washers Ensure Proper, Hassle-free Installation
    • Master Cylinder Stud Thread Size: M10 X 1.5
    • Product Condition: Remanufactured
  • A1 CARDONE Remanufactured Vacuum Brake Boosters, Hydro-Vac Boosters, and Hydraulic Boosters, offer your vehicle reliable stopping performance, every time. Each unit is reverse engineered, based off 40 years of CARDONE Engineering expertise, where original design weaknesses are identified, corrected and where applicable upgraded to provide a more durable part then the original unit. Every unit is remanufactured to meet or exceed OEM performance, providing a quality product both you and your vehicle rely on.
Brand: Cardone
Additional Fitment Information:
Vehicle
1987 - Buick Somerset
Cardone
1992 Buick Skylark Power Brake Booster Cardone - Reman. A-1 CARDONE Vacuum Power Brake Booster w/Master Cylinder

P311-2CAC579    50-1217  Remanufactured

18022006 , 18018168 , 18017215 , 18029988 , 18020889 , 18021929 , 18017552

Qty:
$13.50 $110.85
Cardone Power Brake Booster
  • Remanufactured Vacuum Power Brake Booster w/Master Cylinder
  • Reman. A-1 CARDONE Vacuum Power Brake Booster w/Master Cylinder
  • Product Attributes:
    • Brake Booster Diaphragm Style: Dual Diaphragm
    • Color/Finish: Gray
    • Diaphragm Diameter: 9.030"
    • Features and Benefits:
      • 100% O.e. Quality Seals, Diaphragms And Check Valves Are Installed On Every Unit For Like-new Performance And Reliability
      • All Units Are 100% Tested To Ensure Reliable Performance
      • Exclusive Rust-prohibitive Finishing Process Extends Unit Life
      • Guaranteed Fit And Function
      • Master Cylinder Output Rods Are Pre-adjusted (when Included) For Easier And Faster Installation
      • Meets Or Exceeds O.e.m Performance
      • New Mounting Nuts And Washers Ensure Proper, Hassle-free Installation
    • Product Condition: Remanufactured
  • A1 CARDONE Remanufactured Vacuum Brake Boosters, Hydro-Vac Boosters, and Hydraulic Boosters, offer your vehicle reliable stopping performance, every time. Each unit is reverse engineered, based off 40 years of CARDONE Engineering expertise, where original design weaknesses are identified, corrected and where applicable upgraded to provide a more durable part then the original unit. Every unit is remanufactured to meet or exceed OEM performance, providing a quality product both you and your vehicle rely on.
Brand: Cardone
Additional Fitment Information:
Vehicle
1992 - Buick Skylark
Centric
2007 Buick Rendezvous Power Brake Booster Centric - Centric Power Brake Boosters

P311-3DB10F5    160.80137  Remanufactured

Qty:
$32.00 $155.91
Centric Power Brake Booster
  • Centric Power Brake Booster
  • Centric Power Brake Boosters
  • Product Attributes:
    • California Proposition 65: Warning: Cancer And Reproductive Harm
  • Centric Parts full line of remanufactured brake boosters includes both vacuum and hydraulic units. Each booster is completely inspected, rebuilt and tested to ensure proper fit and function. With over 1,000 applications cataloged, Centric's booster program is the most complete in the aftermarket.
Brand: Centric
Additional Fitment Information:
Vehicle
2007 - Buick Rendezvous
Centric
1996 Buick Riviera Power Brake Booster Centric - Centric Power Brake Boosters

P311-33F8A5D    160.80545  Remanufactured

Qty:
$32.00 $171.96
Centric Power Brake Booster
  • Centric Power Brake Booster
  • Centric Power Brake Boosters
  • Product Attributes:
    • California Proposition 65: Warning: Cancer And Reproductive Harm
  • Centric Parts full line of remanufactured brake boosters includes both vacuum and hydraulic units. Each booster is completely inspected, rebuilt and tested to ensure proper fit and function. With over 1,000 applications cataloged, Centric's booster program is the most complete in the aftermarket.
Brand: Centric
Additional Fitment Information:
Vehicle
1996 - Buick Riviera

Latest Buick Repair and Brake Booster Installation Advice

CarJunky AutoAdvice

1989 Buick Park Avenue ABS Problems

Showing 2 out of 12 Posts | Show 10 Hidden Posts
Question From chrisg7 on 1989 Buick Park Avenue ABS Problems

This will be my first post on these forums, I hope that you all will be able to help me more than the mechanics I've dealt with recently

So a few months ago I was at college and my mom was going to drive my car (1989 buick park avenue ultra ~160,000 miles) to get the yearly inspection. I was told that on the way to the inspection the vehicle started smoking and making some type of noise and the abs light came on. (i should probably note that i had been hearing a rattling noise when driving the vehicle before this) My mom took it to a mechanic who diagnosed it for around $100. He said that it would be around $500 to fix the problem. I did not want to pay that amount of money so i had the car driven back home and decided to deal with it when i got home from school.

A few weeks ago i got back for my winter break. I called the place that originally diagnosed it and they told me that they were sure that the ABS controller was broken, and that the hydraulic pump may also be broken, but i would need to replace the controller first. I ordered a new abs controller off eBay for $120 and got it installed by an auto electric shop for around $90. <-- this is weird because i did some research on the part and was told that it would be somewhere in the $200 range for labor, because some programing work needed to be done on the part, but the electric shop told me that no programming work needed to be done and they just needed to physically install it

After it was replaced, the shop told me that the ABS light was still on, so therefore the problem was not fixed. They said that cars like mine frequently have problems with the ABS pumps, but they would need to diagnose it (another $100!) to find out for sure. I asked them what other components the problem could possibly be and they would not give me a straight answer for some reason.

I would really like advice on what to do in this situation. I am willing to spend maybe $400 more max on this vehicle to get it running. I hope that one of you all can give me some more clear information than these mechanics. If the problem is something that i could fix by myself if i ordered the part, i would be more than happy to learn how to do that.

Response From Hammer Time

We aren't the ones inspecting the car. You have one shop diagnose it and then you think you can save a couple pennies and end up costing you even more. You are not qualified, nor equipped to diagnose a problem like this so you need to let the professional deal with it. You don't get to tell them how much you are going to spend. It is what it is and you will just have to deal with whatever the cost is if you plan on keeping the car.

Response From chrisg7

We aren't the ones inspecting the car. You have one shop diagnose it and then you think you can save a couple pennies and end up costing you even more. You are not qualified, nor equipped to diagnose a problem like this so you need to let the professional deal with it. You don't get to tell them how much you are going to spend. It is what it is and you will just have to deal with whatever the cost is if you plan on keeping the car.

wow that reply was so uncalled for...first off all the first shop was going to do was replace the abs controller. I don't know about you but being a college student with very limited funds, saving $300 is not just 'a couple pennies' to me.

Second, where do you get the idea that i told the shop how much i was going to spend? I gave a price limit in my post because its all i can afford and i will have to sell the vehicle if the repairs require much more than that.

If you are not going to actually take the time to read my post in its entirety and rather just skim it to find ways to criticize someone new to these forums then please do not post in my thread. You are not helping in the slightest with my stressful situation.

I hope that others will give more helpful advice or information. In case the original post was not clear, i was basically wondering what the other causes of my abs light being on could be and if you all had any tips for the best course of action for me. I worry that mechanics are trying to rip me off and i would like to avoid that if possible.

Response From Hammer Time

I worry that mechanics are trying to rip me off and i would like to avoid that if possible.
OH, that comment will get you a lot of help from mechanics donating their time.




I did read your post.


He said that it would be around $500 to fix the problem. I did not want to pay that amount of money so i had the car driven back home and decided to deal with it when i got home from school.


I am willing to spend maybe $400 more max on this vehicle to get it running.

As I told you, it takes some expensive equipment and considerable knowlege that would be utilized in an on site diagnosis. You figured you could buy the part cheaper and find someone to install it cheap. As you have found out now, that idea left you in worse shape than you started. You won't find a magic answer on any forum either because it requires diagnosis with a scan tool to determine what the cause it.

Response From chrisg7


I did read your post.



Yeah my mistake man. I guess you did read my post but just didn't have the intelligence to decipher what i was saying. Let me try to explain to you again so you will hopefully understand.

Originally one problem was diagnosed, a faulty abs controller. The mechanic told me once i fixed this there may or may not be more problems. He said he would charge around $500 to fix it. I instead got the part for $120 and got a mechanic who specialized in electrical components to install it for $90. ($120 + $90 = $210; $210 < $500 ) Turns out there were other problems. So, we can now determine that there were originally at least 2 problems with the entire abs assembly, one of which is now fixed. Because of this, i am in a better situation than i started out in but i still may have a long way to go. Hope that clarifies things for you!

First thing you need to do is figure out what codes the ABS controller is storing to turn the light on. That's if the controller is up and running. Can't even begin to tell you what is wrong unless we have some numbers.

So i'm guessing i need a special diagnostic device to do this?

Thanks for the reply!

Response From Hammer Time

i am in a better situation than i started out in

How do you figure that?

You still have an ABS light on.
You still have no idea why the ABS light is on.
You are a couple hundred dollars poorer now.
That doesn't sound any closer to a solution to me.

Response From Discretesignals Top Rated Answer

I'm going to tell you one thing. If that Powermaster hydraulic control assembly is bad, you might as well look for another car. You get into the thousands trying to fix that problem. How do you know the controller you bought off Ebay is any good? If you really want to keep the car, you could also convert it to regular vacuum brake booster and ditch the ABS.

Response From chrisg7

The seller claimed that all parts were "100% tested and guaranteed to work" and had a good reputation on ebay...not sure how credible that is. I don't know if you can view the link but this is the part i bought
link deleted....not allowed

Could you explain how fixing the hydraulic assembly could get into the thousands? I got a quote for it off this site link deleted..., does it seem legitimate?

Thanks again for all of your help.

Response From Discretesignals

An experienced tech can determine if the controller is bad, the controller isn't getting inputs, the pump motor is shot, has faulty relays or pump switch, the hydraulic control is leaking, or the accumulator nitrogen has leaked out.

It seems like they are guessing to me. Not really that hard to diagnose which part(s) in that system are faulty. When I hear, "Well, we are not sure if this part is going to work unless you replace this one first." I get red flags. You just test each individual part like you would when diagnosing any problem on a vehicle to determine what is broken.

Testing the pump and checking for controller activity and operation isn't too difficult for most techs who know what they are doing.

You might want to have them energize the pump relay and see if the pump comes on before you go buying stuff you might not need. If the pump runs, check to see if the pressure switch circuit opens. You can also ohm out the switch to see if it has continuity when there is no pressure in the system. If the switch checks good but you have no pump operation, Unplug the pump motor connector and check for power and ground in the connector with the relay energized or bypassed. If the pump doesn't come on and you have power and ground to it, needs a pump. Mr. pump motor's power circuit is protected by a fusible link, so if the motor or wiring short to ground, or the motor pulls too many amps, it opens the link. It's important to make sure there is power in the relay cavity.

The controller side is a little more involved, but its circuits can be checked out using a wiring schematic and a DVOM.

Just a little hint:

If you look at the schematic for the pump motor, the controller has nothing to do with the operation of the pump motor anyway. Tell them that...LOL

Response From Discretesignals

I rebuilt a powermaster a long time ago working at the Buick dealer for a customer that had a GN. It was a $2000 ticket. I don't think you can get just the parts for the hydraulic control assembly alone anymore.

You can get a reman hydraulic control assembly, but because they are becoming scarce, they are expensive even with the core. You can also send it in for rebuild, but that is still over a thousand dollars. That doesn't include the labor cost of installation. If you get a used one off Ebay or the salvage yard, your chances of having problems is a whole lot greater.

Your not even sure if that is problem anyway. Needs to be diagnosed properly.

Response From Discretesignals

Yeah my mistake man. I guess you did read my post but just didn't have the intelligence to decipher what i was saying. Let me try to explain to you again so you will hopefully understand.

Yikes....I'll be in another thread. Crap is about to hit the fan.

Response From Discretesignals

First thing you need to do is figure out what codes the ABS controller is storing to turn the light on. That's if the controller is up and running. Can't even begin to tell you what is wrong unless we have some numbers.

06 Lucerne starts but dies right away

Showing 3 out of 12 Posts | Show 9 Hidden Posts
Question From jasecom89 on 06 Lucerne starts but dies right away

I have an 06 Buick lucerne that I bought around 4 days ago. It had 200k miles, v6, and in need of a tune up. I changed the spark plugs and, sure enough, the spark plugs looked pretty bad; in addition, the plugs that were on it weren't iridium (manufacturers specs). I got some iridium spark plugs from autozone but they were not gapped correctly, the specs are .060 and the plugs had .063. I DID NOT gap them, installed them, and now my car won't start and run, no check engine light. If I throttle it to 3k rpms it'll stay running, but not lower.

P.S. It might be worth mentioning that the bank 2 o2 sensor was directly behind my last spark plug, and it may have been "tugged" on accidentally, don't know if that could be it but... Idk

Response From kev2

one thing at a time- you change plugs?
1) you did use AC Delco ?
....... I doubt the .003 will prevent it from starting.
2) when you start vehicle -or try- the CEL should come on @2 seconds fhen go out - yes or no?
....... This I believe will be an issue, so common with used vehicles let us know.
3) Is the security light doing as asked of the CEL?
The o2 sensor would not be an issue in starting... if there was I suspect a code would set- see question #2.

Answer those 1-3 then we will get into BASIC troubleshoting a no statr - do you have a fuel pressure gauge, a DVOM or test light?

PS - A tune up - there is nothing to really 'tune'/adjust SO we are always asking what is you meaning of a tune up.

Response From jasecom89

Yes, I changed the plugs. By tune up I mean maintenance (oil change, new plugs and wires, air filter, etc.). I used Bosch plugs. It starts decently just dies right away unless I throttle. The lights in the dash seem to operate normally (flash on then off at start). I do not have any of the tools you mentioned but can get access to if necessary.

Response From Hammer Time

I used Bosch plugs

Worst possible thing you could have done. Get rid of those things ASAP and tel Autozone right where to stick that junk. Buy AC Delco and nothing else, especially Bosch

Response From kev2

Lets just say the bosch plugs are not recommended.. the are really really NOT recomended

The 3k rpm issue to me would suggest fuel management- very important - I ask again for the status of the CEL aka service engnine soon light- the engine shaped symbol ? on for @2seconds then off ? I believe this is a elec throttle and starting as you describe would be an issue-

Follow GC's advice retrace your work- missed vacuum line, PCV, air inlet ducting disturbed,

Response From Hammer Time

Lets just say the bosch plugs are NOT recommended... seriously.

Let me go a step further.....................

I've had a least 3 vehicles brought to me that other shops couldn't resolve the misfire problem that ultimately turned out to be caused by installing Bosch plugs. They were mostly Fords.

Response From kev2

oops bad grammar - those bosch plugs should go - not recomended.

Response From jasecom89

Well guys, I feel like an idiot.. The brake booster line was not connected... Runs now. Although I did go with ac delco plugs.
Thanks for the help!!

Response From kev2

that large a vac leak and no CEL ? again you should have it scanned and confirm the system works

Response From jasecom89 Top Rated Answer

I failed to mention that what led me to my solution was buying an obd2 and retrieving a pending (no cel, just pending) p0171 code. Googled it and searched for any vacuum leak. The brake booster line was against a flat portion of the firewall. What exactly do you mean 'make sure the system works'?

Response From Hammer Time

Wow, that must have been hissing like hell. At least you found it now

Closing this question as solved.

Response From GC

Was it doing this before changing plugs? Did you use oem plugs?

Start by looking over everything you might have disturbed - sensor connectors,wiring,fuel or vacuum lines. Make sure plug wires are seated on plug and coil. Make sure none got put back on the wrong cylinder.

Have any way to get your hands on a scan tool? Im guessing there is going to be a pending code in there, or might have to access live data to get some direction on where to look.

Front Calipers not releasing

Showing 2 out of 19 Posts | Show 17 Hidden Posts
Question From clatonious on Front Calipers not releasing

1995 buick roadmaster

Front calipers are not releasing 100%. I discovered this issue while replacing the brakes, went ahead and did calipers, rotors, and wheel bearings while in there so I'm all new on both sides (so rule out the obvious like calipers need lube). Both sides will not spin freely and are heating up when driven. If I open either bleeder then they BOTH release...demonstrating it is not a faulty flex hose. Therefore it can only be: A) bad master cylinder, B) push rod out of adjustment (I did buy it used and have no idea what's been done), or C) a bad combo/proportioning valve.

I don't think it's an ABS issue, nothing indicates there's any failure there. I'm trying to avoid just throwing parts at it and would rather diagnose my way through the issue so I'm looking for a way to test each component listed above to see where that last few pounds of pressure is not being released.

I know for starters the push rod adjustment can be tested by breaking the master cylinder free from the booster thus creating slack. So that solves B.

Any suggestions on isolating that unrelieved pressure?

OR, am I missing something else?

PS: I can't see it being an issue of wrong parts, it all fit together precisely as it should have. The only deviance from OEM I've made is the car is lowered on drop spindles and I put ceramic pads on the front. I can't see how either would have any bearing on this issue.

Response From Hammer Time

Therefore it can only be: A) bad master cylinder, B) push rod out of adjustment

I think you hit the nail on the head there.

The next time the brakes are locked up, get the front wheels off the ground and then loosen the hold down bolts to the master and slide it away from the boost by a quarter inch and see if the brakes free up. That will tell you if it's a rod adjustment problem. If that doesn't release them, crack the line loose at the master and see if that does to indicate a bad master.

Response From Tom Greenleaf

Hammer's suggestion is right on target. I can't imagine both flex hoses at once doing this. You may notice unusually little freeplay at top of brake pedal now.

This happened to me just once with a new master cyl that was in fact defective - whole batch was. I can't think of the pushrod being too different after doing brakes unless it was messed with or replaced. Master must let fluid back in of course so is highly likely to have a problem doing that. This is unusual to me for just doing routine brake job but that would explain it,

T

Response From clatonious

**UPDATE**
Jacked up the car this morning and both wheels were fairly free spinning. Started it up and pumped the pedal several times, holding it and such, and eventually they got pretty tight. Cracking it at the master cylinder did free them up.

One more odd thing...since I've gotten the car I've always felt a slight click in the steering wheel whenever I first tap the brakes. My neighbor was helping me today and pointed out that while I was pumping the brakes to get them to lock up the whole booster was flexing (which explains the tapping sensation). As the pedal goes nears the floor (and the piston in the mc nears its end) you can see the flex occur...which would lead one to thing the rod is too long or the pedal out of adjustment.

So I consulted my buick service bulletin on this which tells me NOTHING is adjustable, if rod is too long replace entire booster!


First off the booster is operating just fine.

Secondly, the resistance is right at the end of the pedal run, meaning the piston in the mc is just about fully engaged when the resistance hits, causing the booster to physically flex.

Is it possible that the mc is indeed toast due to A) it releasing pressure by cracking the line and B) having something in it that doesn't allow the piston to fully compress, thus causing resistance to the pedal/rod to the extreme that it actually makes the booster flex against the firewall?

I REALLY don't want to replace the booster, looks to be a super hassle.

Response From Hammer Time

I advised you to loosen the mounting bolts on the master before cracking the line open. Did you ignore that step?

Response From clatonious

ignored is not really the right word but yes I did start with the lines on the mc first because the car is out there and the computer is in here and I didn't remember the order. It's really not a big deal to go through it again because more than anything I want to understand what's going on here...leave it to me to have the flexing firewall.

Just bear in mind there was too much rod (or not enough room left in mc) to begin with otherwise I'd have never felt that sensation in the steering wheel from day one. Also, none of this was a result of the new calipers/brakes/rotors/bearings...I'd noticed the heat before but figured bad caliper.

I'll retest because I see now that cracking the lines would've relieved pressure from the lines OR from the rod...I get it.

BUT the fact remains I am flexing the booster due to too much rod or not enough mc and that's got to tell us something. I cannot believe GM is saying there's no adjustment, and I cannot understand how a rod would grow??? It would make more sense that there's gunk or something in the end of the mc and that's not allowing the piston to get full run.

Response From Tom Greenleaf

Just my two cents for now but I'm not too thrilled with the booster flexing as said? No - never noticed that myself but I also don't ride under a hood when someone slams on the brakes either. Also didn't think pushrod was adjustable on much of anything like this car. For the moment and waiting I think the booster has some strange problem either itself or plain not mounted right??

T

Response From clatonious

I can't find anything to suggest the booster is mounted improperly. Think of it this way...I was splitting wood not too long ago and was into a big old gnarly stump. The wedge buried into it and the pump kept pushing the cylinder out but it had nowhere to go because the wood simply wasn't giving anymore. There was actually enough force to make the heavy channel iron frame start to flex - same thing here.

So I either have a rod that's somehow too long OR an mc piston that cannot travel its full run. I just am trying to figure out which hole to start throwing money at. AND let's not forget this may be totally unrelated to calipers not freeing completely!

I'm hoping there's a collapsed spring in the mc or a bunch of gunk or a bad grommet. New mc and wham bam pressure is relieved and booster rod is allowed to travel its full run unhindered.

Flip side of that coin is that somehow booster rod is too long and 14 hours later whole booster is replaced. Boosters and mc's cost about the same.

Response From Tom Greenleaf

What would be the difference if master was pinned to the bottom vs just the massive force of braking? Nothing. If I read this correctly this problem was there before your brake work - right? Still does it now so being BOTH wheels suggests a problem with either master or booster OR could as DS said the booster just keeps working a bit after you let go?

You have to test the suggestions out already mentioned, we can't. I still don't like it that booster can visually move like that. There's a clue of where the problem is,

T

Response From clatonious

**Update**

Bled the car out totally.
Pumped it up while on blocks, couldn't build much resistance in calipers.
Drove it around a couple miles without brakes being touched, no heat.
Did a couple quick stops, virtually no heat.
Drove it around with light stops, medium heat (could barely touch finger to rotor).
Drove it around as if in city conditions, stopping often, heavy heat (rotors hot enough to fry skin and I could feel heat on my face coming through wheel).
Jacked it back up.
Wheels at this point almost frozen but still turnable.
Pulled booster vacuum line where check valve goes into booster. Pretty significant whoosh sound and wheels suddenly nice and free.
Started it up while still in the air, pumped it a few times till I felt some slight resistance building again, killed it, pulled line and again, smaller whoosh but wheels freed right up.
Blew/sucked into check valve, working properly.

So bad booster?

Response From Tom Greenleaf

None of us are there with your techniques. Of course brakes get hot but how much is near impossible to say on circumstances they were under. You have new brakes so they aren't quite done a full break in yet I think. Right out of the gate with new parts they can take some stops to be at their best - how many depends on the parts and situation too. Brand new they might even give an odor for a few stops.

I never did a brake job without driving a car a couple miles before handing it over to a customer. Not everyone can do that where they work.

If releasing vacuum from the booster frees up the wheels that is interesting. I don't think that should matter as essentially it's just to magnify the force you give it as in "power assisted" brakes which about everything is out there.

Long retired but this isn't all rocket science in a Roadmaster or shouldn't be.

You see the booster move oddly or that's how I understand it without seeing it myself so that's a judgment call. I can't know how hard you pushed and it would show some reaction but nothing to catch attention IMO.

A situation like this to me points towards a bad booster. Can't be sure of anything - this is a website not an actual repair shop being right there with on sight inspection.

For now I think you should consider the booster as the problem but it's still your call,

T

Response From clatonious

Just as an FYI I've put well over 150 miles on the car since the brakes/rotors/bearings/calipers. Like I said, it was sticking before but I assumed bad caliper and thus did the whole 9 yards and just drove normally and softly but it kept eating at me and I started digging.

So anyway I am thinking things are broke in.

I'll give this a couple of days and see if anyone else says much about it and then probably move forward with a booster.

Response From Tom Greenleaf

As said, long retired but still do my own stuff. This is BRAKES and all regulars here don't like tossing parts as a fix but I would call this an exception by what I understand so far. If it was my own I would NOT tolerate a brake problem like that at all. If somehow brakes got way too hot and you didn't notice then call it "fade" and they may not work well or worse terrible and an accident that could be avoided over chasing this down even if it takes a few bucks is cheap.

Quick look showed them as "remans" for under $100 (exchange for yours) or a deposit lost. I doubt this one is that difficult and haven't had the fun of doing one on any of these cars but probably takes some tools to get at the thru bolts, unhook the rod to get out starting from underdash. Just nuts on studs that go thru firewall. If enough flex in master cyl to move it still intact shouldn't be that hard but could be wrong.

It seems to be the common denominator of the problem. If it makes you feel better let a tech look at the problem and you can decide on DIY or what. Now you could look to see the 3-4 nuts the hold it and the rod and know if you can get at them with the tools available to you.

It's your responsibility to make this car stop properly if not for yourself for innocent other(s.) If you can't or don't want to finish out a perfect diagnosis let a shop take care of it. The car must stop. Going is not my concern with this.

Do the right thing,

T

Response From clatonious

UPDATE

New MC, new booster, new back brakes (needed done anyways), new fluid of course and survey says.................same problem still.

Only 2 things haven't been replaced new front to back now - combo valve and front hoses (of which no test really pointed that way).

So, I'll replace the both of them....which leaves the final option - the ABS junction/system.

I understand how the combo or hoses would still be the issue but can someone explain how the ABS box or system would be behind this?

Response From Hammer Time

Or you could just perform the test that you were asked to in the beginning and loosen the master cylinder mounting bolts to find out once and for all if the pressure is originating at the master.

Response From clatonious

OR you could realize that MC means master cylinder and A) that test was done and B) I put a new one on read above

Hey thanks for the help genius...great board you're running here

Response From Hammer Time

You're getting one warning and one warning only. Don't run your mouth around here or you will be gone in a heartbeat.

You may think you know it all but you really don't. A new master cylinder does not eliminate an incorrect push rod adjustment. There are ways to test for all these issues instead of your method of simply throwing parts at it.

Response From Tom Greenleaf

This is too important to wait. Fix it now. This is only web site not there in person or some things might be obvious.

Do the right things to fix this. No head games with Hammer Time or any body. Here for free to help so you get your money back in full - ZERO.

Nice round #. No problems folks, if you don't like this place just go away - easy! Many of us can do that for you!

Tom

Response From Discretesignals Top Rated Answer

Also before you unbolt the master from the brake booster to see if the brakes release, pull the booster check valve out of the booster to relieve the vacuum in the booster to see if the booster is the culprit. Seen that happen on a few cars.

79 Buick Wont Start

Showing 2 out of 4 Posts | Show 2 Hidden Posts
Question From mcclellan1214 on 79 Buick Wont Start

1979
Buick
Lesabre Limited Sedan
4.9 L 301 CID 2 BBL Carb Automatic 3 speed
~220,000 miles

I drive this car as my everyday driver, it has a V8 and still gets decent gas mileage. Last winter I had major issues with it starting in cold weather, it wouldn't turn over fast enough for the engine to fire. It would just flood itself out, I would have to hook up a battery charger to get it started. (Carburetors, gotta love em) I eventually had enough with it flooding that I bought a new battery with 850 CCA, new top post terminals and put it in. For an entire year it started great with no problems. Now this year it is doing the same thing but worse. I drove it four hours one day to my cdl school, four days of starting in cold weather the battery drained itself. Classmates helped me jump it again and still no luck, I looked around the carb and noticed a bad vacuum line. it had cracks on either end, I taped them for temporary fix. I got in and it fired after the first revolution like there was nothing wrong with it. To be on the safe side I let it sit but started it everyday and night to assure it would start for my trip home.
The last day it started up just fine and ran even better than before, I drove it more than 200 miles to a gas station and shut it off. It turned over about 8 times before it fired again, so I drove it home and parked it. the next morning I got in it to start it and it turned over very slowly about five times and the battery went almost completely dead. I waited for my girlfriend to get home to jump it and after ten minutes of charging it did the same thing, turned over until the battery drained and did not fire. Now the interior electronics work but no sound from starter or battery at all. WHAT SHOULD I DO??? PLEASE HELP.

Response From Discretesignals

This should take care of it.





Original engine? Did you replace all the crusty vacuum hoses? Any vacuum leaks?

Response From mcclellan1214

I replaced the ones that I saw were horrible, everything on this car was original when I got it even the brake pads still had gm orange paint on them.

Response From Tom Greenleaf Top Rated Answer

Sounds like the last Pontiac small V8 but not your issue. Battery seems like it isn't charging so check the voltage before and after running.

Top posts? Whatever you did to change that check that again. If just cheapo u-clamps those suk. Can still use a spliced in top post clamp just get real good ones.

Battery could be toast already no matter how new so charge it and test it. You are saying you get interior lights but no response from starter so connections or battery are high on the list. Plain lighting doesn't take much, starter take lots! Generally if just low will flutter the solenoid. Nothing at all is way too low.

Vacuum lines anywhere: Just do them all one by one so you don't mix them up. Cheap for parts, just some time. Cut any on plastic vacuum trees with a razor and peel off. Those break off easily and no glue found to me will fix them now would be near impossible to find.

Do larger vacuum hose to brake booster too which is specific hose that wont collapse under vacuum and marked probably for PCV or fuel use on it.

That wasn't the worst carb. Try the next few years right after 1979!

If the Pontiac and you want tons more out of this car do check the timing chain as they ate them for lunch - poor lubrication even on replacements,

T

My Buick is acting up

Showing 2 out of 23 Posts | Show 21 Hidden Posts
Question From jackx on My Buick is acting up

I got a 1999 Lesabre. It has been throwing a P0135 trouble code. I looked it up and that's a
upstream O2 sensor code. I cleared the codes and ordered a new O2 sensor.

Now its runs fine but every so often it will die. It always starts right up when I hit the ignition.
It died twice today when I was slowing down at a stop light. Then it died as it was just coasting
along at about 30 mph.

Its not throwing a code and its got 1/2 tank of gas. I guess it could be the fuel pump not putting
out enough pressure. I'm not sure how to determine what the pressure is when it is acting up. I hate
to just drive it till it is obvious it does not have enough fuel pressure by waiting until it won't start.
It primes with my fuel pressure showing 45 pounds of pressure and after it starts my guage shows
41 or 42 pounds of pressures. When you give it gas the pressure will go back up to about 45 pounds.

I looked up what the pressure has to be in order to start the motor. I found it won't start unless it has
48 pounds of pressure. Since my car starts ok it must be getting 48 pounds of pressure and I guess
my guage is 3 pounds off. So, since is starts I guess the fuel pressure may be ok.

I guess it could be the crankshaft position sensor. Maybe its needs to be cleaned or replaced. It's not
throwing a code.

I guess it could be a ignition problem but I don't know what could be the problem since its not
throwing a code.

Any body got any suggestions as to how to determine why its dying.

Response From Hammer Time

This is one of the hardest problems to resolve. What has to be do is you have to hook up diagnostic tools to monitor spark, injector pulse and fuel pressure and you have to be watching them at the exact moment the car dies and determine which one cut out first.


In the meantime I would at least clean the throttle body.

. Remove the intake snorkel, have someone hold the throttle wide open for you and scrub the back side of the throttle plate and surrounding bore with an old tooth brush and some carb cleaner. Be sure to spray some into the small holes next to the throttle plate.

Response From jackx

Yeah if that is what you have to do then I am in trouble.Unfortunately it only stalls now when you are
rolling down the road.

I will clean the throttle body and see if it stops stalling.

Its got the same fuel pump and crank shaft position sensor it had when I bought it. That was
5 years ago and it only had 63,000 miles on it then. Since it has 109,000 miles on it now and those
parts were probably the same ones that came on it from the factory I may have to replace
them unless the problem becomes not a intermittent problem. At least that gives me an idea of
how much this could cost to fix if I can identify the problem and these components need to be
replace. Probably a $200 problem.

I'll just drive it and maybe store the local tow truck number in my cell phone....At least it starts
when it dies.....

I may take it to a shop after I drive it a few more days. A shop can probably can give me an idea
on what they find is usually the problem and I will take it from there. Unfortunately they may just
have to start replacing parts. I hate it when they want to do that.

All I know is you basically need 3 things to get a motor to run.
fuel
spark
compression

If its the pump then its "fuel'
and if its the crank shaft position sensor its "spark"

Response From Hammer Time

No, a Crank sensor will take out spark and fuel.

I might gamble on changing a Crank sensor but i doubt the fuel pump is the issue here. It could even be a computer or maybe cleaning the throttle bold will resolve it.

Response From jackx

Thanks for the help.

Been checking and it only takes 45 pounds of pressure to start a lesabre.
So, my gauge is probably giving me the right number and the pump is probably not the problem.

If cleaning the throttle body with some carb cleaner does not solve the problem then I am thinking
I will pull the connector off the crank shaft position sensor and see if it needs some electrical
cleaner.

Response From Discretesignals

They can start on 14 lbs of fuel pressure, but they'll bog out when you rev em. This doesn't have poppet valves that require a certain amount of pressure to open them.

Like HT stated, accurately diagnosing an intermittent stall and restart issue is very difficult. Sure you can get lucky changing parts out, but how much you will to spend on guesses and what happens if it is a circuit issue?

Someone is going to have to monitor systems to see what fails when the glitch occurs. Even professionals with years of drive-ability experience can find those challenging.

Response From jackx Top Rated Answer

I pulled the snorkel off the 3.8 motor. I also pulled the MAF sensor out of the housing that the
snorkel mounts on. There is a screen over the snorkel opening and you can't actually see the butterfly
valve. I squirted Berryman B12 through the Screen and moved the throttle linkage so the
Berryman should have squirted on both the top and bottom sides of the Butterfly. I also squirted
some Berryman down the hole I pulled the MAF sensor out of. I was careful not to get any
Berryman on the MAF sensor and I cleaned it good with CRC MAF cleaner. Then I started the
motor. I had to push the pedal to the floor because it was flooded. It started. I then pulled the
vacuum hose off the brake booster, turned the linkage to rev it up and I poured 1/2 a can of Seafoam
slowly through the vacuum hose. I poured the remaining Seafoam in the tank.

I drove it around the block a few time and the throttle seemed more responsive and it did not
stall. This is good because earlier when I went to autozone to get the Berryman and Seafoam it
stalled on the way home at a stop sign. I guess after I drive it a few days I will know if it is
good to go. I will update you then. I will keep my fingers crossed. If it doesn't fix it I will take the
housing off so I can actually see the butterfly and again try to clean it with the Berryman. Hopefully
I cleaned it enough that it won't stick again.

Thanks for you help.

Response From Tom Greenleaf

Agree with the guys this type thing is a pest on techs and people. Great - runs new then nothing for no reason then runs new again and everything checks out - arrr!


Done with this game mostly but not that long ago same bull same basic set up you have for a Winter beater car pulled that. OK, ready now with fuel pressure gauge on it and spark presence thing inline plus a momentary push button (think they still sell those) to trigger starter with key left on such that in that case you see what's missing IF IT DOESN'T START RIGHT UP!


No fuel and now spark like you. No codes to help on that one either. I think it was a crank sensor and still wouldn't know like you for sure without a period of time of it not happening or toss any possible thing that could do that.


Too late as car was free and worth as much as scrap as playing with it so to the bone yard it went and regret it now as it was a totally legal good running worst looking thing though car to just use up. It's not amusing with those sudden "I'm not running right now no matter how inconvenient it is with no warning" so sit there and I'll think about it to get you home - didn't cut it with me but should have gone for it.


I/we hate the parts toss game but if car is nice enough count that expense vs the royally annoying surprise strandings!


T

Response From jackx

Drove it and it died about 3 times and as I rolled up the drive and it died again ......

I started it and blipped the throttle. I noticed it would only rev up so much and then it would start
to heave and surge. Tried it again and the same thing.

I went ahead and pulled the housing off the snorkel buckles up to so I could get to the butterfly
valve. Four bolts and it came off and whow the butterfly and the inside of the housing was coated in
thick black muck.

I got my Berryman B12 and hosed her down. I used the toothbrush just like Hammertime said to do
and finally got it clean. I did clean both sides of the butterfly valve.

I had pulled the MAF out again before I hosed it with B12 and hosed it down with CRC MAF cleaner.

I don't know if its fixed but now no more surging when you blip the throttle.

I got to drive it back the same route as I went this afternoon again tomorrow and I guess I will
see if its fixed or not....Got my fingers crossed.

Thanks for the help.

Response From Discretesignals

Really don't think your out of the woods.

You'll probably need to fix the O2 sensor code. Check the O2 heater resistance. If it is open, replace the sensor. You'll need an accurate sensor to look at O2 voltages and fuel trims when it comes to that time.

Another possibility is the O2 could be sticking rich which causes the engine computer to lean out the fuel. It really easy to see this with a scan tool. On some of the early ones, the programming wasn't smart enough to stop trimming when an O2 sensor was stuck. They would actually lean or rich the engine out so much it would cause stalling, rough running, lack of power, etc. Dodge and GM were really bad about that in the early days when O2 sensors stick.

Response From jackx

Well I agree.

I just went to the store and on the way back it died just going down the street. I put it in
neutral and it started back up and I made it back home.

I know it needs a O2 sensor but I will have to wait until it gets here. It cost half as much as the same
one at Autozone but I won't get it til the 10th.

Can you explain how I can use a volt meter to test the O2 sensor to see if it is bad. It has a square
female connector. It is the upstream sensor. I know there is a signal wire and a ground. I also know
two of the wires are the same color and they go to the heater circuit of the sensor.

I erased the P0135 O2 SES code. I didn't think it would be a problem until it was driven long enough
for the computer to do its diagnosis and then it would throw a code again. Its thrown this code before
and it did not do what it is doing now.

I've considered disconnecting the MAF to see if would run right not using the MAF to regulate the
fuel injectors. I can do this to see if it cures the problem because it will be a while before I get that
new Bosh O2 sensor. I know it will throw a code but I can always erase it.

I've also wondered if the MAP could cause it to die like it is doing. I've got the same one in my pickup that I could
put in the Lesabre to see if it cures the problem. What do you think?

I guess after I eliminate these as possible cures I will end up probably deciding the crank shaft position
sensor is the problem. I will start looking for some utube video on how you remove and replace one of these
sensors. I have been putting that off.

I sure wish they would throw a SES code so I would know what the problem is.

Response From Discretesignals

MAF sensor can cause stalling, hesitation, and loss of power. MAP sensor won't do that.

If the computer is receiving a MAF signal and not coding some type of MAF code, MAP sensor isn't even being used by the engine computer for load calcuations. The MAP is used for BARO readings, to see if EGR is flowing, and as a back up if the MAF goes kuput.

You could unplug the MAF and go into back up mode, to see if your stalling goes away. If your stalling stops, it could be MAF or MAF circuit issues. It will code for a MAF circuit issue when you unplug it.

The O2 sensor wires that are the same color are the heater circuit wires. Just probe those two terminals for those wires in the O2 sensor connector cavity with an ohm meter. If you have an open circuit, O2 heater is shot and needs a sensor.

As your stated the other two wires are signal and sensor ground. You can actually see the O2 sensor voltage back probing the connector on the signal wire. The voltage will swing between 0-1.0 volt when the sensor is operational. It is a lot easier to see this on a scan tool though because you can see how the computer reacts to the voltage the sensor produces.

Response From jackx

I unplugged the MAF and it would not idle right and would just barely run.

I plugged it back in and cleared the code.


I thought it would run ok and it doesn't make sense that it would barely idle.

Maybe the sensors that provide it input to know how much fuel and air are

needed are bad but aren't throwing a code. I know the MAP and Throttle Position

sensor are use to make it run if the MAF is disabled. Maybe the MAP sensor is

causing the O2 sensor to throw a code. I also suspect the TPS sensor could cause

it to die too but since it's not throwing a code and isn't a factor when the MAF is

connected it is probably not the problem.

Response From Discretesignals

That is strange. Once it reverts to back up mode, it shouldn't run like dog crap. Your going to need to look at scan data.

TPS usually doesn't cause stalling unless it is shorting the 5 volt ref to ground.

Response From jackx

It was not running and the switch was not on when I disconnected the MAF sensor.

Response From jackx

I may have got some Berryman B12 on the TPS when i was cleaning the throttle body. If I did
that probably caused it to give a bad signal to the ecm. That could make it cause the wild i
dle when I removed the MAP and it could also make it die. I will let it dry tonite. I will check
it again tomorrow to see what happens when I disconnect the MAF again.



If it still idles crazy I may need a new TPS. I found this on a website I googled up for :
" can a tps cause a lesabre to stall"

"ENGINE STALLING

This generally occurs when rapidly decelerating to a standstill, though it can also happen while idling. Again, without accurate information, the computer cannot deduce how much fuel to inject, so it averages the amount used in the last few moments of operation. When the throttle suddenly snaps shut, the engine is starved of air while the injectors are still delivering part-throttle amounts of fuel. The effect is very similar to rapidly closing the choke on an old manual-choke equipped truck."

link deleted ....................... not allowed

A bad TPS would also explain why it won't idle when the MAF is disconnected

I may get one tomorrow.

Response From Discretesignals

This generally occurs when rapidly decelerating to a standstill, though it can also happen while idling. Again, without accurate information, the computer cannot deduce how much fuel to inject, so it averages the amount used in the last few moments of operation. When the throttle suddenly snaps shut, the engine is starved of air while the injectors are still delivering part-throttle amounts of fuel. The effect is very similar to rapidly closing the choke on an old manual-choke equipped truck."

Stalling can occur at any engine speed and any throttle position. That statement is inaccurate. When the throttle is snapped shut the IAC or ETC acts as a dash pot to bring the idle down.

Maybe it is time for a shop that specializes in drive-ability to have a look at it. I don't see any testing going on, only wild guesses and part swapping idea.

Response From jackx

I let it set overnite. I was still was thinking the TPS had B12 on it. I wanted to let it dry out some.

I pulled the MAF connector off. It did not rev up or anything this time. Lots better. It seemed to idle ok but
when you blipped the throttle it acted like it was missing. I turned it off and replaced the
MAF connector and cleared the code. Started it and it sounded great. I did notice that the
MAF and TPS have the screws in them that require a special screwdriver that I don't have. Nuts.....
I used a pair of pliers to take those screws out of the MAF but I can't get the pliers on the
ones on the TPS.

There is another sensor mounted back and under the MAF sensor that does not have those screws.
I pulled it off. It had a plunger on it that was dirty, I cleaned it off with B12 and put it back on. I
suspect it is the Idle control module. Under it is what appears to be the TPS. Since it had those
screws I left it alone.

Later today I will go ahead and rewire the pigtail on the new O2 sensor and put it on. I will
drive it some and see if still dies when I am coasting along or stopping. I do know cleaning that
butterfly really did make it respond a lot better to the throttle but there may be other problems
that also need to be addressed.

I don't have the testing equipment and I think I will take descrete's advice and start looking for a shop that
can fix this thing by performing whatever tests are necessary to determine what is actually
causing the problem. All these parts are expensive and I sure don't want to buy any that don't
actually need to be replaced.

Its always possible that since the TPS seems to be working better this morning
that it may be ok now. It could have been that ecm can't read the MAF sensor sometimes
when I am slowing down and when it reverts to the backup system the bad TPS caused it
to die. Its possible I guess that the TPS could even be causing the problem even if the
MAF sensor system was being used by the ECM. I really don't know what component or components are
bad but I am sure someone out there will be able to figure it out if I can just find them.

Thanks again for you help.

Response From Hammer Time

I think this thread has run it's course as DS pointed out. Advice isn't being followed and no actual testing is being done.

Response From Hammer Time

I think your theory about getting cleaner in the TPS is all wet. There is really no path for that to happen from inside the throttle body.

It's pretty asy to simply test the TPS if you have any doubts. If you have a reader with data you can monitor that or you can just use a DVOM

Response From jackx

Yeah it was all over the place after I started it up.

It revved up and then it idled back down and started to

try to die and then it would rev up again. Weird.....

I have a new O2 sensor that I can put in tomorrow but I

will have to put a square connector on it. I got the

one for a lesabre but it did not fit because during the

year they switched to a square connector. Its been setting

around for a year or so. I'll go to Ace hardware and get some

butt splice connectors and install it tomorrow, Then maybe

I will have a good O2 sensor that may be my whole problem. I

really hate to suffer with this thing til the 10th when the

one I ordered gets delivered.

Response From jackx

Well disconnecting the MAF was a bad idea. It would barely run. I cleared the
code.

I'll wait on the O2 sensor. maybe it will get me around til then.

Response From Discretesignals

Did you unplug the MAF with the engine running? Unplug it with the key off. Then start the engine.