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    Standard Ignition
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Best Selling Genuine Volkswagen Oxygen Sensors

  • We Stock the following top leading brands, including Delphi, Bosch, Denso
  • Constantly Updated Inventory of Volkswagen Replacement Oxygen Sensor Parts

We stock Oxygen Sensor parts for most Volkswagen models, including Beetle, CC, Cabrio, Cabriolet, Corrado, Eos, EuroVan, Fox, GTI, Golf, Jetta, Passat, Phaeton, Quantum, R32, Rabbit, Rabbit Convertible, Rabbit Pickup, Routan, Scirocco, Super Beetle, Tiguan, Touareg, Transporter, Vanagon.

Delphi
2005 Volkswagen Phaeton Oxygen Sensor Delphi

P311-50B8426    W0133-1768890  New

Qty:
$130.82
Delphi Oxygen Sensor
  • Forward Exhaust Manifold
Brand: Delphi
Free Ground Shipping on this item
Additional Fitment Information:
Vehicle
2005 - Volkswagen Phaeton
Bosch
1982 Volkswagen Quantum Oxygen Sensor Bosch

P311-2B3907B    W0133-1614661  New

Qty:
$43.35
Bosch Oxygen Sensor
  • Disc
  • Two required
  • - 2 Required
Brand: Bosch
This Product is Eligible for Free Ground Shipping
Additional Fitment Information:
Vehicle
1982 - Volkswagen Quantum
Denso
2009 Volkswagen Routan Oxygen Sensor - Downstream 6 Cyl 3.8L Denso

P311-55CD38B    234-4588  New

Qty:
$22.86
Denso Oxygen Sensor  Downstream
  • 4 Wire, Direct Fit, Heated, Wire Length: 18.7
  • OE Style
  • DENSO oxygen sensors are manufactured and tested to the strictest OE standards for unparalleled peformance; Each component is precision built for exact replacement, and a first time fit; This innovative line features DENSO's exclusive aluminum oxide trap layer, designed to protect the ceramic element from silicone and lead posining for improved engine performance, greater fuel efficiency, and unparalleled longevity; DENSO gives you the right part and the right fit, the first time.
Brand: Denso
Additional Fitment Information:
Vehicle Block CC CID Position
2009 - Volkswagen Routan V 3778 231 Downstream
Denso
2009 Volkswagen Routan Oxygen Sensor - Downstream 6 Cyl 3.8L Denso

P311-55CD38B    234-4588  New

Qty:
$22.86
Denso Oxygen Sensor  Downstream
  • 4 Wire, Direct Fit, Heated, Wire Length: 18.7
  • O.E. Quality Replacement Sensor
  • OE Style
  • DENSO oxygen sensors are manufactured and tested to the strictest OE standards for unparalleled peformance; Each component is precision built for exact replacement, and a first time fit; This innovative line features DENSO's exclusive aluminum oxide trap layer, designed to protect the ceramic element from silicone and lead posining for improved engine performance, greater fuel efficiency, and unparalleled longevity; DENSO gives you the right part and the right fit, the first time.
Brand: Denso
Additional Fitment Information:
Vehicle Block CC CID Position
2009 - Volkswagen Routan V 3778 231 Downstream
Denso
2002 Volkswagen Passat Oxygen Sensor - Downstream Left Denso

P311-3AE22B9    234-4809  New

Qty:
$58.81
Denso Oxygen Sensor  Downstream Left
  • 4 Wire, Direct Fit, Heated, Wire Length: 36.42
  • OE Style
  • DENSO oxygen sensors are manufactured and tested to the strictest OE standards for unparalleled peformance; Each component is precision built for exact replacement, and a first time fit; This innovative line features DENSO's exclusive aluminum oxide trap layer, designed to protect the ceramic element from silicone and lead posining for improved engine performance, greater fuel efficiency, and unparalleled longevity; DENSO gives you the right part and the right fit, the first time.
Brand: Denso
Additional Fitment Information:
Vehicle Position
2002 - Volkswagen Passat Downstream Left
Denso
2002 Volkswagen Passat Oxygen Sensor - Downstream Right Denso

P311-3AE22B9    234-4809  New

Qty:
$58.81
Denso Oxygen Sensor  Downstream Right
  • 4 Wire, Direct Fit, Heated, Wire Length: 36.42
  • OE Style
  • DENSO oxygen sensors are manufactured and tested to the strictest OE standards for unparalleled peformance; Each component is precision built for exact replacement, and a first time fit; This innovative line features DENSO's exclusive aluminum oxide trap layer, designed to protect the ceramic element from silicone and lead posining for improved engine performance, greater fuel efficiency, and unparalleled longevity; DENSO gives you the right part and the right fit, the first time.
Brand: Denso
Additional Fitment Information:
Vehicle Position
2002 - Volkswagen Passat Downstream Right
Denso
2002 Volkswagen Golf Oxygen Sensor - Downstream 6 Cyl 2.8L Denso

P311-3AE22B9    234-4809  New

Qty:
$58.81
Denso Oxygen Sensor  Downstream
  • 4 Wire, Direct Fit, Heated, Wire Length: 36.42
  • OE Style
  • DENSO oxygen sensors are manufactured and tested to the strictest OE standards for unparalleled peformance; Each component is precision built for exact replacement, and a first time fit; This innovative line features DENSO's exclusive aluminum oxide trap layer, designed to protect the ceramic element from silicone and lead posining for improved engine performance, greater fuel efficiency, and unparalleled longevity; DENSO gives you the right part and the right fit, the first time.
Brand: Denso
Additional Fitment Information:
Vehicle Block CC CID Engine Designation Position
2002 - Volkswagen Golf V 2792 - BDF Downstream
Denso
2002 Volkswagen Passat Oxygen Sensor - Downstream Left Denso

P311-3AE22B9    234-4809  New

Qty:
$58.81
Denso Oxygen Sensor  Downstream Left
  • 4 Wire, Direct Fit, Heated, Wire Length: 36.42
  • O.E. Quality Replacement Sensor
  • OE Style
  • DENSO oxygen sensors are manufactured and tested to the strictest OE standards for unparalleled peformance; Each component is precision built for exact replacement, and a first time fit; This innovative line features DENSO's exclusive aluminum oxide trap layer, designed to protect the ceramic element from silicone and lead posining for improved engine performance, greater fuel efficiency, and unparalleled longevity; DENSO gives you the right part and the right fit, the first time.
Brand: Denso
Additional Fitment Information:
Vehicle Position
2002 - Volkswagen Passat Downstream Left
Denso
2002 Volkswagen Passat Oxygen Sensor - Downstream Right Denso

P311-3AE22B9    234-4809  New

Qty:
$58.81
Denso Oxygen Sensor  Downstream Right
  • 4 Wire, Direct Fit, Heated, Wire Length: 36.42
  • O.E. Quality Replacement Sensor
  • OE Style
  • DENSO oxygen sensors are manufactured and tested to the strictest OE standards for unparalleled peformance; Each component is precision built for exact replacement, and a first time fit; This innovative line features DENSO's exclusive aluminum oxide trap layer, designed to protect the ceramic element from silicone and lead posining for improved engine performance, greater fuel efficiency, and unparalleled longevity; DENSO gives you the right part and the right fit, the first time.
Brand: Denso
Additional Fitment Information:
Vehicle Position
2002 - Volkswagen Passat Downstream Right
Denso
2002 Volkswagen Golf Oxygen Sensor - Downstream 6 Cyl 2.8L Denso

P311-3AE22B9    234-4809  New

Qty:
$58.81
Denso Oxygen Sensor  Downstream
  • 4 Wire, Direct Fit, Heated, Wire Length: 36.42
  • O.E. Quality Replacement Sensor
  • OE Style
  • DENSO oxygen sensors are manufactured and tested to the strictest OE standards for unparalleled peformance; Each component is precision built for exact replacement, and a first time fit; This innovative line features DENSO's exclusive aluminum oxide trap layer, designed to protect the ceramic element from silicone and lead posining for improved engine performance, greater fuel efficiency, and unparalleled longevity; DENSO gives you the right part and the right fit, the first time.
Brand: Denso
Additional Fitment Information:
Vehicle Block CC CID Engine Designation Position
2002 - Volkswagen Golf V 2792 - BDF Downstream
Denso
2004 Volkswagen Phaeton Oxygen Sensor - Downstream Right 12 Cyl 6.0L Denso

P311-3AE22B9    234-4809  New

Qty:
$58.81
Denso Oxygen Sensor  Downstream Right
  • 4 Wire, Direct Fit, Heated, Wire Length: 36.42
  • Loc. Front O.E. Quality Replacement Sensor
  • OE Style
  • DENSO oxygen sensors are manufactured and tested to the strictest OE standards for unparalleled peformance; Each component is precision built for exact replacement, and a first time fit; This innovative line features DENSO's exclusive aluminum oxide trap layer, designed to protect the ceramic element from silicone and lead posining for improved engine performance, greater fuel efficiency, and unparalleled longevity; DENSO gives you the right part and the right fit, the first time.
Brand: Denso
Additional Fitment Information:
Vehicle Block CC CID Position
2004 - Volkswagen Phaeton W 6000 - Downstream Right
Denso
2004 Volkswagen Phaeton Oxygen Sensor - Downstream Right 12 Cyl 6.0L Denso

P311-3AE22B9    234-4809  New

Qty:
$58.81
Denso Oxygen Sensor  Downstream Right
  • 4 Wire, Direct Fit, Heated, Wire Length: 36.42
  • Loc. Rear O.E. Quality Replacement Sensor
  • OE Style
  • DENSO oxygen sensors are manufactured and tested to the strictest OE standards for unparalleled peformance; Each component is precision built for exact replacement, and a first time fit; This innovative line features DENSO's exclusive aluminum oxide trap layer, designed to protect the ceramic element from silicone and lead posining for improved engine performance, greater fuel efficiency, and unparalleled longevity; DENSO gives you the right part and the right fit, the first time.
Brand: Denso
Additional Fitment Information:
Vehicle Block CC CID Position
2004 - Volkswagen Phaeton W 6000 - Downstream Right
Denso
2004 Volkswagen Phaeton Oxygen Sensor - Downstream Left 12 Cyl 6.0L Denso

P311-3AE22B9    234-4809  New

Qty:
$58.81
Denso Oxygen Sensor  Downstream Left
  • 4 Wire, Direct Fit, Heated, Wire Length: 36.42
  • Loc. Rear O.E. Quality Replacement Sensor
  • OE Style
  • DENSO oxygen sensors are manufactured and tested to the strictest OE standards for unparalleled peformance; Each component is precision built for exact replacement, and a first time fit; This innovative line features DENSO's exclusive aluminum oxide trap layer, designed to protect the ceramic element from silicone and lead posining for improved engine performance, greater fuel efficiency, and unparalleled longevity; DENSO gives you the right part and the right fit, the first time.
Brand: Denso
Additional Fitment Information:
Vehicle Block CC CID Position
2004 - Volkswagen Phaeton W 6000 - Downstream Left
Denso
2004 Volkswagen Phaeton Oxygen Sensor - Downstream Left 12 Cyl 6.0L Denso

P311-3AE22B9    234-4809  New

Qty:
$58.81
Denso Oxygen Sensor  Downstream Left
  • 4 Wire, Direct Fit, Heated, Wire Length: 36.42
  • Loc. Front O.E. Quality Replacement Sensor
  • OE Style
  • DENSO oxygen sensors are manufactured and tested to the strictest OE standards for unparalleled peformance; Each component is precision built for exact replacement, and a first time fit; This innovative line features DENSO's exclusive aluminum oxide trap layer, designed to protect the ceramic element from silicone and lead posining for improved engine performance, greater fuel efficiency, and unparalleled longevity; DENSO gives you the right part and the right fit, the first time.
Brand: Denso
Additional Fitment Information:
Vehicle Block CC CID Position
2004 - Volkswagen Phaeton W 6000 - Downstream Left
Denso
2002 Volkswagen Golf Oxygen Sensor - Downstream 6 Cyl 2.8L Denso

P311-3AE22B9    234-4809  New

Qty:
$58.81
Denso Oxygen Sensor  Downstream
  • 4 Wire, Direct Fit, Heated, Wire Length: 36.42
  • O.E. Quality Replacement Sensor BDF Engine
  • OE Style
  • DENSO oxygen sensors are manufactured and tested to the strictest OE standards for unparalleled peformance; Each component is precision built for exact replacement, and a first time fit; This innovative line features DENSO's exclusive aluminum oxide trap layer, designed to protect the ceramic element from silicone and lead posining for improved engine performance, greater fuel efficiency, and unparalleled longevity; DENSO gives you the right part and the right fit, the first time.
Brand: Denso
Additional Fitment Information:
Vehicle Block CC CID Engine Designation Position
2002 - Volkswagen Golf V 2792 - BDF Downstream
Denso
2004 Volkswagen Phaeton Oxygen Sensor - Downstream Right 12 Cyl 6.0L Denso

P311-3AE22B9    234-4809  New

Qty:
$58.81
Denso Oxygen Sensor  Downstream Right
  • 4 Wire, Direct Fit, Heated, Wire Length: 36.42
  • O.E. Quality Replacement Sensor Loc. Front
  • OE Style
  • DENSO oxygen sensors are manufactured and tested to the strictest OE standards for unparalleled peformance; Each component is precision built for exact replacement, and a first time fit; This innovative line features DENSO's exclusive aluminum oxide trap layer, designed to protect the ceramic element from silicone and lead posining for improved engine performance, greater fuel efficiency, and unparalleled longevity; DENSO gives you the right part and the right fit, the first time.
Brand: Denso
Additional Fitment Information:
Vehicle Block CC CID Position
2004 - Volkswagen Phaeton W 6000 - Downstream Right
Denso
2004 Volkswagen Phaeton Oxygen Sensor - Downstream Right 12 Cyl 6.0L Denso

P311-3AE22B9    234-4809  New

Qty:
$58.81
Denso Oxygen Sensor  Downstream Right
  • 4 Wire, Direct Fit, Heated, Wire Length: 36.42
  • O.E. Quality Replacement Sensor Loc. Rear
  • OE Style
  • DENSO oxygen sensors are manufactured and tested to the strictest OE standards for unparalleled peformance; Each component is precision built for exact replacement, and a first time fit; This innovative line features DENSO's exclusive aluminum oxide trap layer, designed to protect the ceramic element from silicone and lead posining for improved engine performance, greater fuel efficiency, and unparalleled longevity; DENSO gives you the right part and the right fit, the first time.
Brand: Denso
Additional Fitment Information:
Vehicle Block CC CID Position
2004 - Volkswagen Phaeton W 6000 - Downstream Right
Denso
2004 Volkswagen Phaeton Oxygen Sensor - Downstream Left 12 Cyl 6.0L Denso

P311-3AE22B9    234-4809  New

Qty:
$58.81
Denso Oxygen Sensor  Downstream Left
  • 4 Wire, Direct Fit, Heated, Wire Length: 36.42
  • O.E. Quality Replacement Sensor Loc. Rear
  • OE Style
  • DENSO oxygen sensors are manufactured and tested to the strictest OE standards for unparalleled peformance; Each component is precision built for exact replacement, and a first time fit; This innovative line features DENSO's exclusive aluminum oxide trap layer, designed to protect the ceramic element from silicone and lead posining for improved engine performance, greater fuel efficiency, and unparalleled longevity; DENSO gives you the right part and the right fit, the first time.
Brand: Denso
Additional Fitment Information:
Vehicle Block CC CID Position
2004 - Volkswagen Phaeton W 6000 - Downstream Left
Denso
2004 Volkswagen Phaeton Oxygen Sensor - Downstream Left 12 Cyl 6.0L Denso

P311-3AE22B9    234-4809  New

Qty:
$58.81
Denso Oxygen Sensor  Downstream Left
  • 4 Wire, Direct Fit, Heated, Wire Length: 36.42
  • O.E. Quality Replacement Sensor Loc. Front
  • OE Style
  • DENSO oxygen sensors are manufactured and tested to the strictest OE standards for unparalleled peformance; Each component is precision built for exact replacement, and a first time fit; This innovative line features DENSO's exclusive aluminum oxide trap layer, designed to protect the ceramic element from silicone and lead posining for improved engine performance, greater fuel efficiency, and unparalleled longevity; DENSO gives you the right part and the right fit, the first time.
Brand: Denso
Additional Fitment Information:
Vehicle Block CC CID Position
2004 - Volkswagen Phaeton W 6000 - Downstream Left
Bosch
2000 Volkswagen Passat Oxygen Sensor - Downstream 6 Cyl 2.8L Bosch

P311-40C6811    15733  New

Qty:
$50.91
Bosch Oxygen Sensor  Downstream
  • Bosch is the OE equivalent supplier
  • Universal Oxygen Sensor
  • Product Attributes:
    • Automotive Color / Finish: Steel
    • Connector Shape: None
    • Housing Material: Metal
    • Installation Hardware Included: Universal Connector Kit
    • Mounting Type: Threaded
    • Thread Diameter: 18
    • Universal Or Specific Fit: Universal
    • Wire Quantity: 4
  • Suggested Purchase Quantity: 2
    • Most jobs typically require 2 of this item.
Brand: Bosch
Additional Fitment Information:
Vehicle Aspiration Block Body CC CID Position
2000 - Volkswagen Passat Naturally Aspirated V Sedan 2771 - Downstream

Latest Volkswagen Repair and Oxygen Sensor Installation Advice

CarJunky AutoAdvice

stuck

Showing 2 out of 8 Posts | Show 6 Hidden Posts
Question From tg2020 on stuck

I have a2002 Volkswagen passat and it just cut out on me while I was driving it. Before it cut out the oil light kept coming on and telling me to stop the car, it kept doing that for a few days before it totally went out. I had previously taken it to checkers for a reading but the guy couldn't understand the code I guess and he didn't give me the code. I had just gotten and checked my oil and it wasn't low, I also had gas in it. How can I figure out what's wrong without paying an arm and leg to have it towed and diagnosed?

Response From Hammer Time

That's OK. If you continue to drive it when the warning lights tell you to shut it down, you'll be needing a new car anyway.

I had previously taken it to checkers for a reading but the guy couldn't understand the code I guess

Sounds like you use real experts for advice too.

Response From tg2020 Top Rated Answer

I am open to any advice, I have had independent mechanic look at our too, but they are up front about foreign cars being hard to work with. I wish I could afford a new car, but I just paid this one off . It no longer starts or anything, I was once told my oxygen sensor was funny but nothing alarming. Like I said I'm open to any knowledge of these cars.

Response From alexayers08

since you are here i assumed you googled to get some idea of what could be wrong? i posted on here and got a little bit of help but it mostly came from other places, the mechs that help here are stuck in their ways and can only help if you know what the problem is... If i knew the problem i could fix it without them thats why i came here

Response From Discretesignals

the mechs that help here are stuck in their ways and can only help if you know what the problem is.

Alexayers08, maybe you should stick to your own problems and stop creating other problems. If you have a problem with a mod in here, contact another mod or the site admin through private message.




Tq2020, If it doesn't want to start, but it cranks, you would want to follow the basics of seeing what is missing to cause it not to start.

http://autoforums.carjunky.com/Automotive_Repair_C1/General_Discussions_F5/IF_YOUR_STARTER_CRANKS_THE_ENGINE_BUT_IT_WILL_NOT_START_P75655/

If you don't have the knowledge or equipment for diagnosing no start problems your going to have to find a licensed repair shop that specializes in European vehicles or the VW dealer, even if that means having to go to a different city.

Response From Hammer Time

Before it cut out the oil light kept coming on and telling me to stop the car, it kept doing that for a few days before it totally went out.

I don't have high hopes for this engine

Response From Hammer Time

alexayers08 So, I guess you will be fixing your car yourself next time.

We are professional mechanics here that donate our time to help out. We spend a lot of money in test equipment and training. We don't use crystal balls as many of you seem assume. If you don't appreciate the help, go elsewhere.

Response From kev2

Sorry - the vehicle has 'issues' evident by the warning lights AND the code retrieved from the on board diagnostics scan.
There is no working around the need for some diagnostics, guessing is costly, are you capable of and do you have the tools to perform checks- fuel pressure, electrical, ignition, and oil pressure ? Maybe we can walk you thru some basics.

Stalling troubles in a 98 VW Beetle

Showing 4 out of 4 Posts
Question From thebug87 on Stalling troubles in a 98 VW Beetle

Three days ago my car started having some problems. I would be able to drive my car for about 15 minutes before it would shut off. I tried to restart the car and the engine turned over but wouldn't catch. After about 10 minutes the car started and I drove it home. I checked the oil level, air filter, fuses, and coolant. The following day I drove the car to my dad's and the same stalling issue occurred and it restarted after 10 minutes and I continued driving to my destination. At this point my car had about a little under half a tank of gas. We checked the vacuum in the gas tank, which seemed all right. I then drove the car for a while to make it stall, once stalled we turned the key and it would turn over, but, not catch. We then immediately opened the gas cap and the car turned over leading us to believe there is an issue with the vacuum in the fuel tank. We have since driven the car for over an hour and it has not stalled, however, the gas level is now lower than a quarter of a tank. So I am back to square one. The check engine light is always on in the car so I cannot tell if a sensor is bad.
The car had similar stalling issues two years ago and the crank sensor was replaced. Four years ago the oxygen sensor was replaced.
We are going to check the mass air flow sensor and lights. Any other suggestions would be greatly appreciated.

1998
Volkswagen Beetle
2.0 L
145,000 Miles

Response From Tom Greenleaf

With the CEL light lit there's a code or more to read for guidance on what the issue is. Get the code(s) -

T

Response From thebug87

Thanks for the advice, but, I am trying to avoid getting the codes read for two reasons: 1 - The light is always on because there is something wrong with the signal and 2 - I priced the dealership and cost is about 150 just to read the code.

Response From Tom Greenleaf Top Rated Answer

You shouldn't have to go to a dealer to get a comprehensive code reading. Many parts outlet do that for free to sell parts of course and they may not give a complete answer or have a good of equipment.

I know if it costs something it's still worth it as you have a problem and that could certainly help. Think - you could be saving a mega expensive repair to fix something now.

No harm in ruling out things you can see or find like things not attached properly, wiring plugs, vacuum hoses etc.

Tune and other maintenance needs to be up to date. It could just be getting bad info and trying to make adjustments and when it can't it will set a code,

T

Old Car Performance/Efficiency Suggestions

Showing 2 out of 33 Posts | Show 31 Hidden Posts
Question From RoboDisko on Old Car Performance/Efficiency Suggestions

Hey, I've got an old car. 84 Volkswagen Jetta (1.8L engine) with 237,000 on it. I got it fairly recently from a friend, and I was wondering what some of the things I should do to it to increase performance and efficiency are.

So far I have taken my injectors off and cleaned them, and lightly cleaned the throttle body. I think I messed up one of the injectors in the process, and it seems to run rougher, and the injector seals are hard as rocks, so I was planning on pulling some newer style but compatible injectors, with new O rings, from a jetta at the junk yard, after ultrasonically cleaning them. I am also planning on pulling the cat off, because a 30 year old cat with no maintenance probably isn't helping anyone. I am also considering changing the manual transmission oil, because the current stuff might be stock.

I also think i messed up the fuel to air ratio. When I got it, the exhaust smelled like fuel, so I adjusted the fuel to air ratio until the exhaust no longer smelled like fuel. I think the reason it smelled like fuel is because, as I recently noticed, it does have an oxy sensor, but it wasn't plugged in, so I think it was making the mixture as rich as the system was able to automatically adjust for. Keep in mind this has a mechanical fuel injection system. (K-Jetronic I'm pretty sure, google it)

Some other thoughts on it. It doesn't idle very smoothly. Sometimes it idles smoother than other times, but in general I think it should be smoother. Also, I've noticed that the difference between half-throttle and full-throttle is miniscule. Not sure what would cause that. I also know the alignment isn't right, because my front left tire is almost bald while the other tires are in good condition.

My friend that I got the car from said he was getting 30+ mpg from it. So far, on my first fill up I got about 18 mpg, (I had some major timing issues that I think had a big impact on that) and 24 mpg on my second fill up. Its going up :), but I hope to be able to touch the 40's with this car :/. Also, when he had this car, he usually drove 80 miles at a time, and when I use it, I rarely go more than a mile, so the engine is still cold when I get there most of the time.

Ok, I know this car has problems, but what are my priorities in fixing it? Anything I haven't mentioned that I need to look at? Anything else?

Response From Hammer Time

84 Volkswagen Jetta (1.8L engine) with 237,000 on it

The word performance should never leave your lips when you are talking about this car. With that kind of mileage, if you abuse this engine in any way you are going to end up with nothing but a big boat anchor with no engine. You may get a few more miles if you baby it and maintain it well but if you beat on it, it's going to die.

Response From RoboDisko

I think I know someone that has a compression checker, I will see if I can borrow it and check.

Also, a piece of metal is a piece of metal, in my opinion. I don't think that just because an engine has provided enough energy to travel 237k miles means that it is a baby. However if the cylinder walls are oval, then yea... Let's stick with the compression check and then go from there.

Also, I have a friend that own a junkyard with a few more of the same engine. If this engine goes boom, I've got another one :) although that doesn't sound like fun :(

I should mention that I am more interested in efficiency than performance.

Response From Hammer Time

All the bearings in that engine have 237K on them and there can't be much left. The oil pump has done more work than it's designed to and you can say that engine is on borrowed time from here on.

Response From Tom Greenleaf

Whole car is 30 years old - every last moving anything. Plastics and rubber things all over go brittle, springs, seating hinges latches even wiring insulation and connections and so on. Point is it's not just a brick of metal, T

Response From RoboDisko

Fair enough. And now that you mention it, my friend did give me this car for free because it had broke down, the problem being that the ground for the ignition module had come off of the battery. But I can repair and replace wires as they go. Reliability isn't a big deal anyways, since I rarely go more than 5 miles from my house, and I'm not afraid to try to fix it on the side of the road.

Still trying to get access to a compression checker...

Response From Tom Greenleaf

Compression tester:
/
In stock item almost anywhere! Probably rentable but only about $25 bucks.


Totally not adverse to older vehicles. Just know to go thru check and fix certain things pro-actively or declare one not practical any more for the time it would take or raw expense of parts to make one legally useful for public roads,


T

Response From RoboDisko Top Rated Answer

FINALLY GOT A COMPRESSION TESTER!
Like a month later I know :)
Someone I know owns a mechanic shop and he loaned me his. He warned me that it was damaged but usable. Without anything connected it 0'd at 25 psi. So I think the readings are at least 25 psi higher than real. It also didn't hold the pressure, so I had someone crank it while I recorded the peak value. The values I recorded are:
1. 177 psi +-3
2. 177 psi +-3
3. 177 psi +-3
4. 177 psi +-3
They were all darn close so I just rounded to the same number. They were all between 175 and 180 though.
Because the meter 0'd at 25 psi and because it is well used, I think subtracting 30 psi from each would get us a more accurate number.
I interpret the data as all cylinders with 147 psi +-8.

From what I have read that is a good psi and so I shouldn't have any compression-related issues, although I am open to other opinions. So, what can I do that is relatively easy and relatively cheap that would help the engine run better. I am already working on the fuel system. I know it is running lean, and I have ordered a new oxygen sensor/injector O rings/fuel filter and I will set the combustion ratio when they come. What else?

Response From Tom Greenleaf

You really are looking for them all to be close to each other, 4th bounce up while cranking and it locks that pressure as cylinder would leak down. Then small squirt of oil to see the difference that makes especially if one is off from another and so on.


Accuracy of the actual PSI# I wouldn't be way too worried about. A real nice gauge would have a screw to set to zero.


You can also get a good clue from a vacuum gauge on crude mechanical engine wear - all this to know what you are dealing with.


You mentioned you seek "efficiency" and it's prior long run at a time use is naturally going to do better than short runs not even warmed up.


Think: World's largest cruise ship and most fuel efficient moped are both getting ZERO MPGs sitting still and it goes from there. Just make it to run as well as possible and you are there and there are no magic tricks short of pushing it or towing it to alter efficiency much.


It's sarcastic but just make all your trips downhill with a tailwind roundtrip helps


T

Response From RoboDisko

All of the PSI values I measured were very close. Also, the gauge I was using leakes and you have to be watching it while you crank.

Anyways, after I measured all of the PSI values on Monday, I put the spark plugs back on and parked it. The next day I noticed that something was wrong. When I rev the engine it sounded like 1 or 2 of the cylinders wasn't firing right or at all. And when you give it some fuel to accelerate, there seemed to be a 1-2 second delay before I got most of the acceleration force. For example, I shift into 3rd and give it some fuel. It slowly accelerates for 2 seconds, and then I can feel a small jerk as it starts to accelerate much more quickly. Let go of the fuel and shift to 4th, and this happens again. In addition, I have killed the engine several times lately because it doesn't have the power it used to have.

On Tuesday I thought, "No big deal. I probably forgot to plug a spark plug wire in or messed up the gap." Well today I pulled my plugs, cleaned them, checked the gap, and re-tested the compression. The #2 plug was very black like it was running very rich. I didn't pay much attention to the plugs on Monday, but I don't think it was that black. As for the compression:
1. 150 PSI!!!!!!!!! This was 180 on Monday, what happened?!
2. 180 PSI
3. 180 PSI
4. 176 PSI
#1 cylinder with a cap of oil in it: 160 PSI
FYI firing order is 1-3-4-2
Ok, my car was running well on Monday, and now it sounds and runs like a trash can. What could have messed the #1 cylinder up so much? What should I check? What should I do?
The guy that loaned my the compression tester gave 2 suggestions. He said he thought it was running rich (I'm still planning on tuning the f/a ratio, but I thought it was running lean), and the valve springs. I believe he owns a mechanic shop, but I didn't give him as much description as I have given you.

Video of the issues my car is having:

Response From Tom Greenleaf

OK - Vid only showed that it sounds like crap as you sad.


Your tester is in question so that ends most of that. I did show what looks like a single putt out tail pipe as if one cylinder is not firing properly. If that cylinder is cold, fuel washed compression would be off or something alarming.


Just in handling plugs and wires could have harmed them?


I'll try to paste a basic idea of how to take compression or if it doesn't show right remove it. Engine somewhat warm. Plugs out, marked for correct location with wires. Spark and fuel disabled.


Crank and watch pulse increase compression #. By 4th rev it should be about what it can do.


KEY IS EVEN MORE THE TEST THAN THE exact # you get. Oil test will seal lower end things more like rings, cylinder wall wear mostly if dramatically changed by that more inspection to find out. You didn't have dramatic so forget that. Wet test will not change valve issues.


In your case engine is running so lousy in that vid that I think test results are inconclusive. Might behave if it was stone cold and move on to other reasons if compression is within 10% or so.


That black plug is telling of problem there. Wire, plug itself, over fueled etc. Heat clean and swap it for another or replace with new plugs OE for an engine. Leave tricks for the last run to the salvage yard.


It's open book on this. IMO a fussy and old car with plenty of miles. Right now compression is in question and something else my be the cause as said fuel or ignition. IDK why two test showed so differently except for the known leaky tester? Guess you could move on to a leak-down test on that cylinder?
---------------------------------------


I just said most of this but just some fool thing I found out there on compression test. I don't agree with it totally but the idea there....................

Difficulty: EasyTime Required: 30 MinutesHere's How:

  1. Let the car run for about 5 minutes, you always want to compression test a warm engine for best results.
  2. Disable the ignition system so the engine does not fire up during testing.
  3. Label the spark plug wire with the same number as you label the spark plug hole, 1 through 6 for example, before removing all the spark plugs.
  4. Insert the compression tester into the cylinder spark plug hole labeled #1 and tighten by hand only.
  5. Have your helper crank the car’s engine 7 to 10 times continuously to obtain the most accurate reading on the compression gauge.
  6. Record the reading for the cylinder labeled #1 and remove the tester from the spark plug hole.
  7. Make sure that the pressure gauge returns to zero before continuing testing and recording the rest of the cylinders while the engine is still warm.
  8. Clean and replace the spark plugs with the correct spark plug wire.
Tips:
  1. The compression test is not so much about the absolute level of compression; it is the difference in the compression between each of the cylinders. If all cylinder readings are within 10 percent of each other, your engine compression is considered optimal. However, if any of the cylinders compression vary 10% or more from each other, a problem may exist and further inspection of the engine should be completed.





+++++++++++++++++++++++++++++++++


T

Response From RoboDisko

Those steps you posted are almost exactly what I did. I feel fairly confident that the PSI values I got both times are fairly accurate. I had double checked #1 cylinder on Monday, and I triple checked it today, with consistent results. Right now I'm not so concerned about cylinder #2 because I am about to redo f/a ratio anyways. But what should I do about cylinder #1?

Response From Tom Greenleaf

I plain don't know what you mean by adjusting air to fuel ratio on this or if so if you can target ONE cylinder.


If #1 is really off it will effect the overall show. At TDC on that one apply pressure and see where it leaks. Let's rule out plain wear on this thing.


If you can see if wires will fit another and the problem follows checking misfiring at a cylinder or cancel them one at a time to focus in better. RPM if just one will stay the same if one is dead and canceling that one doesn't change anything. A good one on a 4 cylinder with one bad cylinder would stall out no doubt.


* If cancelling a cylinder by taking off plug wire ground it as if just left hanging that spark might seek other routes confusing that test. This is crude basic testing. Any wires and plugs don't like being fussed with, dropped, pulled wrong or even good stuff will be harmed messing up diagnosing.


Keep trying and keep the investment low IMO. Rent, borrow and swap known good things within that car to a known bad and follow is cheaper than tossing all for a maybe on things.


For finding random or one cylinder not behaving without wild tools you can feel the pulse at tail pipe and usually tell just don't burn yourself please, use a rag if you do that.


I don't think converter is the issue on this for just this right now.


For whenever or soon if still not nailing it, a vacuum gauge test can be informative also. Takes stuff/tools even for the most basic things,


T


#1 compression funky and #2 with fuel fouling apparently

Response From RoboDisko

Interestingly enough, the k-jetronic lambada fuel system that my car is equipped with allows you to adjust the fuel going to each cylinder. However, some further tests seem to eliminate that cylinder #2 is getting excessive fuel in comparison to the other cylinders. Here is what I did.
I pulled the spark plug wires one at a time, and then two at a time, and then three at a time, and then four at a time. (I'm just kidding about the four at a time) Anyways, with only 1 cylinder firing, I could keep the engine running on each of the cylinders except #2. For the most part, cylinder #2 didn't fire at all. Occasionally, it fired a few times sequentially, and then stopped firing again. Cylinders #3 and #4 seem to be running absolutely fine.

I KNOW that cylinder 1 leaks, because I put one of the compression checker tubes on that didn't have a 1-way valve, blew into it, and I could feel the air go into the cylinder. I turned the engine several times to make sure it wasn't just on the intake or exhaust stroke. I did this on the other 3, and when they weren't on intake or exhaust, they felt air-tight.

I am planning on hooking a compressor to the #1 cylinder using the compression gauge adapter without a 1-way valve, and then listening and feeling for the leak location. I am also planning on taking the #2 spark plug out and seeing if it fires when not in the cylinder.

I would rather deal with the compression issues on cylinder #1 before tackling the combustion issues on cylinder #2. Or maybe one of the gaskets between the cylinders developed a leak recently? Anyways, I am open for any suggestions at this point.

I think it is worth mentioning that I used a flash light on a spark plug hole to see inside the cylinder, and it looked really dirty. Like, there were spots that one could see the metal, but most of the surface area was covered by black stuff, presumably carbon. It was like this in both cylinder #1 and #2, I didn't look into #3 or #4. Is that normal? Does that affect performance? How would one go about cleaning carbon in the combustion chambers?

Response From RoboDisko

Someone please reply to this and say "random" because I got into my car to pick up the compression gauge again, and it was running great again! All I did was take the #2 fuel injector out and put it back in... Anyways, on further inspection, it seems than #2 is firing normally again. I was hoping that #1 also was up to 180 PSI, but it was not, still at 150 PSI. After that, I hooked up the 1-way valve-less adapter to the cylinder, and my compressor to the adapter. After establishing that anything over 40 PSI was enough to turn the engine until it hit an intake or exhaust stroke even when in 5th gear, I discovered that it seemed that the air was leaking into the cam-case. (I don't know if that is the technical term) When I took off the oil lid thing, which is directly above the cam and above #1, I can hear a rather strong hiss, and I think I can feel some air come out.

I could be wrong, but I think there is a leak on the top of the #1 combustion chamber. There are 2 reasons I think this: the above mentioned compressor test, and the fact that putting oil in the cylinder did not have a significant affect on the compression PSI. I also don't think it is the valves because I couldn't hear or feel air comping out of the intake or exhaust. What part of the engine would allow pressure to leak out of the top of the combustion chamber? What other things should I try?

Response From RoboDisko

Ok, I feel like I am on a wild goose chase. Checked the compression again:
1. 176
2. 177
3. 175
4. 178

Also, I put the compressor to all 4 of the cylinders, and they all made the same mild hissing sound coming out of the oil pour hole. So maybe the head gasket is a bit worn? I'm just guessing here, you guys are the pros. I have a spring break coming up and I wouldn't mind getting in over my head in an engine repair like a head gasket. But would it help? Or am I just crazy?

Response From Tom Greenleaf

OK: Oil test remains unproven. Guess to be verified is that #1 needs better leak-down test but might be intermittent which is troublesome by itself but a gasket could allow it's compression into no useful place in cylinder #2 throwing off proper firing and complicating even that one getting correct useable spark, fouled plug from fuel or if metal shaving ground out plug that ends that. Consider cylinder wash and more.


High miles for this engine let alone age. May need to pull head to get a good look to see it this engine is even worth your time!


T

Response From RoboDisko

Ok what I am thinking is I can pull off the head and do a partial overhaul. Clean the cylinders, replace head gasket and header gaskets, valve gasket, replace the valve springs if then need it, clean up valves and camshaft, ultrasonic clean anything that fits in my little ultrasonic cleaner, and put it all back together. Would that be worth my time? Is that way over my skill level? Can I get a time estimate, cost estimate, steps and some advice?

As a side note, I decided it was time to patch some exhaust leaks, and it quickly escalated to my exhaust getting cut right behind the cat. I'm planning on bypassing the cat, cleaning the exhaust pipe, and patching the holes, but it sure is fun to drive without a muffler. I knew it was going to be loud, but it is louder than I expected. There is a kid at my school that probably has $50K into his truck, probably several thousand just in his exhaust, loves blowing black smoke clouds. Anyways, I was passing him opposite direction and I pushed the clutch in and revved it, and his jaw dropped. It was awesome. Especially the fact that I have put less than $150 into my car, $110 of that was the stereo, and the car itself was free.

I know I am going to have to put the muffler back on if i don't want to get tickets, but it is sure fun to drive without it.

Anyways I would like several opinions on if the partial overhaul I proposed would be practical.

Response From Hammer Time

I'm planning on bypassing the cat,

You do realize that is against Federal law and carries a fine up to $25,000?

Response From RoboDisko

I meant remove the cat. Yea I know it's illegal, but my dad has been running his car without the cat for over 10 years. In addition, vehicles over 25 years are exempt from emission testing, and where I live doesn't do emission testing anyways. In more addition, this cat is over 30 years old, has been through rich and lean. Do you think there is anything left?

I would be surprised if the cat is still functional at all. Just in the time I have had it, I had 1 cylinder that wasn't firing, sending a ton of unburned fuel to the cat. If it is not doing anything, and if I am not going to get caught for it, then I see no reason to leave it on. Do you?

Response From Hammer Time

None of that changes the fact that it is illegal to remove it without replacing it with a new one. I doubt you will find a shop willing to do that.

Response From RoboDisko

:) you don't know me. Half of my friends are in automated manufacturing. Plasma lasers, lasers, welders, grinders, metal benders, cnc machines, all manned by a bunch of teenagers. I know a shop that will do it for me. How do you think I took my muffler off anyways?

Also, I would really appreciate if we can get away from the morality of removing my cat and get back onto how feasible it is for me to pull the head off. Thanks.

Response From nickwarner

I think you pulling off the head is feasible. I think you having a running engine when you are done is not.

Response From Discretesignals

You shouldn't be pulling anything apart until you have absolutely isolated your problem, unless your into that sort of thing. Compression numbers look fine. You can also do a dynamic compression test on that cylinder you believe it having an issue to see if you have an engine breathing problem. A static compression test won't tell you if the exhaust valve isn't opening.

Haven't played around with any K jet fuel systems that one has, but it does have an O2 sensor. You could scew a back pressure gauge in place of the O2 sensor and measure that amount of back pressure in the exhaust before the cat to see if you have an excessive amount of restriction going on. That would save you the time and expense of removing the exhaust system.

Is this vehicle going to be your daily driver or are you wanting to turn it into a race car?

Response From RoboDisko

Daily driver race car that gets great mpg, of course!

But really, if you haven't got the contest clues, I'm 17 in high school. My high school is acrossed the street, so if my car dies it really isn't a big deal. I am currently very interested in working on my car. Spring break is next week, which would be a great time to take the head off. From what I understand, what that would entail is the following:
1. Take timing chain cover off (I think it is a chain)
2. Take timing chain off, take note of timing positions so it can be put back on properly.
3. Take valve cover off.
4. Probably some bolts and bearings holding the cam. Remove them.
5. Remove the cam.
6. Remove exhaust and intake manifolds.
7. Find head bolts and remove them.
8. Remove the head?
9. Clean all parts thoroughly.
10. Reassemble in opposite order, putting gaskets where necessary.
11. Fresh oil?
How close am I? Obviously each step is fairly large, but taking them 1 at a time can't be too hard, right?

Anyways Discretesignals , I have already used a recip saw right behind the cat, and it would take about as much time to measure back pressure as it would to simply remove the cat.

Also, this isn't the first engineering I have done. As a one man team, I went to nationals for robotics, and ranked in the upper half. I know how to build and maintain efficient mechanical things.

As for a dynamic compression test, I don't think I have any of the tools that would require. I don't know where I would find the tester, and I don't plan on buying one.

What do you guys think I should do?

Response From Tom Greenleaf

Quote"How close am I? Obviously each step is fairly large, but taking them 1 at a time can't be too hard, right?"


You don't even own a compression tester or able to borrow one that I believe yet and going to take on this? Trust me, it will be a learning experience but will never run again, even poorly.

You have to do your diagnosing before tearing into it. At best if you did a perfect job, sent head out and all fine the lower end could give up fast.

This could have cracked magor parts you can't see at all without some tests.

Soooooo, you've got essentially no investment in the thing and unless somehow this car is in exceptional shape in all other aspects just part it out before you lose your shirt. It's worth something as just metal by weight,

T

Response From RoboDisko

You have a point. I don't plan on parting out my car. As far as metal weight, this thing is one of the lighter cars on the road. I think it is under 2K lbs.

Besides that the head, what other fun mods could I do to it? I was reading about water injection, which sounded interesting.

Response From Tom Greenleaf

Water injection now! Did someone lace something you ate?


You lost about $100 for a junk converter already as even dead ones are good for the metals they use. Rest of car call local salvage for what they would pay for whole vehicle delivered or if they pick it up.


A couple ways you could make some bucks would be to find a good party for St. Patrick's Day, paint some shamrocks all over it and get a baseball bat and charge $5 buck a whack at it for the fun of it.


Do what you want but you clearly are NOT in any position to make this a decent running car from the read of this thread.


It's your $$ but I'd start off the learning thing with something that at least runs well right away and work on details not something that is quite this hopeless - your call,


T

Response From RoboDisko

The car is running pretty well right now. I just would like to make it run better.

Response From Discretesignals

General rule of thumb is don't modify your daily driver. If your daily driver was running bad and had problems, you would have to diagnose and repair those problems. If this is something you drive to school or work everyday, you don't want to play around with modifying and racing it because you depend on it.

Majority of people that own race cars also have daily drivers that are bone stock and reliable. You really can't have both in one, unless you have lots of money laying around and not too concerned about breaking down or breaking things.

Being young and wanting to go fast is a normal thing for a teenager to dream about, especially with all the Fast and Furious related movies around. The reality is as you get older you start to realize things aren't cheap and your constantly paying bills, trying saving money, and working you hind off to make things meet.

I'm not trying to be a parental figure, but giving you the realities of life.

Response From RoboDisko

Although it is my daily driver, I can easily do without it, and that is why I am not afraid of taking a chance with it. My high school is acrossed the street, and the tech center (part of school) is like 1/4 mile away. I do have a bike.

I also try to be very conservative with my limited funds, and have never watch Fast and Furious movies. I just like building things.

So what are some fun mods I could do to the engine? Preferable low cost and low risk ones.

Response From RoboDisko

I just took a flash light to my cat, and it is COMPLETELY HOLLOW. No honeycomb structure AT ALL. It is simple a large hollow black area. I was hoping to get performance improvements... Do you still think removing it will help?

Response From Discretesignals

First thing you should do is run a compression check on it. Make sure the battery is fully charged, the ignition and fuel systems are disabled, and the throttle is wide open when you perform your compression test. Write down the numbers for all cylinders. Post them in here, so we can see what your dealing with.

If the engine is tired, messing around with the other things is a waste of time.