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Shop By Brand

The Following brands are available based on your search.

  • Cardone
    Cardone
  • Dorman
    Dorman
  • Mopar
    Mopar
  • Standard Ignition
    Standard Ignition

Best Selling Genuine Dodge Vacuum Pumps

  • We Stock the following top leading brands, including Dorman, Standard Ignition, Mopar, Cardone
  • Constantly Updated Inventory of Dodge Replacement Vacuum Pump Parts

We stock Vacuum Pump parts for most Dodge models, including D250, D350, Dart, Durango, Journey, Ram 2500, Ram 3500, Sprinter 2500, Sprinter 3500, W250, W350.


Dorman
2003 Dodge Sprinter 3500 Vacuum Pump 5 Cyl 2.7L Dorman

P311-09566BD    904-848  New

5117674AA , SK904848 , 6112300265

Qty:
274.40
Dorman Vacuum Pump
  • ; Mechanically Driven
  • Product Attributes:
    • Inside Diameter: 0.311 In.
    • Mounting Hardware Included: No
    • Pulley Included: No
    • Relief Valve: Yes
    • Vacuum Pump Connector: Barbed
    • Vacuum Pump Drive System: Belt Drive
    • Vacuum Pump Inlet: 0.311 In.
Brand: Dorman
Additional Fitment Information:
Vehicle Block Engine CID CC
2003 - Dodge Sprinter 3500 L 5 Cyl 2.7L 165 2687
Dorman
2006 Dodge Sprinter 2500 Vacuum Pump 5 Cyl 2.7L Dorman

P311-206E067    904-836  New

68038549AA , 6462300365 , 5117675AA

Qty:
268.03
Dorman Vacuum Pump
  • ; Mechanically Driven
  • Product Attributes:
    • Inside Diameter: 0.320 In.
    • Mounting Hardware Included: No
    • Pulley Included: No
    • Relief Valve: Yes
    • Vacuum Pump Connector: Barbed
    • Vacuum Pump Drive System: Gear Drive
    • Vacuum Pump Inlet: 0.320 In.
Brand: Dorman
Additional Fitment Information:
Vehicle Block Engine CID CC
2006 - Dodge Sprinter 2500 L 5 Cyl 2.7L 165 2687
Dorman
2004 Dodge Ram 3500 Vacuum Pump 6 Cyl 5.9L Dorman

P311-5E9A91D    904-214  New

53032373AB , 53032373AA , 6C3Z2A451BA , F81H2A451B , VDV23 , F81Z2A451BA , 7C3Z2A451B , VCP132 , 4C3Z2A451BA , BRPV7 , 64-1509 , 7V1006 , 53032373AC , VP8 , VCP112 , 6C3Z2A451A

Qty:
86.07
Dorman Vacuum Pump
  • ; Electrically Driven
  • Product Attributes:
    • Pulley Included: No
    • Relief Valve: No
    • Vacuum Pump Connector: Barbed
    • Vacuum Pump Drive System: Electric Motor Drive
    • Vacuum Pump Inlet: 1/4 In.
    • Vacuum Pump Outlet: 1/8 In.
Brand: Dorman
Additional Fitment Information:
Vehicle Block Engine CID CC
2004 - Dodge Ram 3500 L 6 Cyl 5.9L 359 -
Dorman
1989 Dodge W350 Vacuum Pump 6 Cyl 5.9L Dorman

P311-4B98A8C    904-809  New

4429103 , 64-1300

Qty:
100.51
Dorman Vacuum Pump
  • ; Mechanically Driven
  • Product Attributes:
    • Pulley Included: No
    • Relief Valve: Yes
    • Vacuum Pump Connector: Barbed
    • Vacuum Pump Drive System: Gear Drive
    • Vacuum Pump Inlet: 3/8 In
    • Vacuum Pump Outlet: 3/8 In
Brand: Dorman
Additional Fitment Information:
Vehicle Block Engine CID CC
1989 - Dodge W350 L 6 Cyl 5.9L 359 -
Standard Ignition
2005 Dodge Ram 3500 Vacuum Pump 6 Cyl 5.9L Standard Ignition

P311-334E102    VCP142  New

5102084AA , EC1425 , 64-1027

Qty:
1,131.72
Standard Ignition Vacuum Pump
  • Vacuum Pump
  • Product Attributes:
    • Hardware Included: No
    • Hose Connector Quantity: 1
    • Hose Size - Inches: 3/8"
    • Notes: Vacuum
  • Direct-fit OE replacement properly restores pressure to ensure efficient running of vehicle accessories. High-quality O-rings and seals prevent leaks and maintain proper vacuum pressure. Precision-cut vacuum pump pulley shaft ensures exact OE dimensions for proper fit and easy installation. Undergoes 100% pressure testing to prevent leaks and ensure OE-matching performance. As a global manufacturer, we maintain complete quality control throughout the manufacturing process.
Brand: Standard Ignition
Additional Fitment Information:
Vehicle Block Engine CID CC
2005 - Dodge Ram 3500 L 6 Cyl 5.9L 359 -
Standard Ignition
2018 Dodge Durango Vacuum Pump 6 Cyl 3.6L Standard Ignition

P311-57E6274    VCP145  New

EC1428 , 4581954AB

Qty:
256.32
Standard Ignition Vacuum Pump
  • Vacuum Pump
  • Product Attributes:
    • Hardware Included: No
    • Hose Connector Quantity: 1
    • Hose Size - Inches: 3/8"
    • Notes: Vacuum
  • Direct-fit OE replacement ensures proper fit, form, and function, which leads to a trouble-free installation. High-quality O-rings and seals prevent leaks and maintain proper vacuum pressure. Undergoes 100% pressure testing to prevent leaks and ensure OE-matching performance. As a global manufacturer, we maintain complete quality control throughout the manufacturing process.
Brand: Standard Ignition
Additional Fitment Information:
Vehicle Block Engine CID CC
2018 - Dodge Durango V 6 Cyl 3.6L 220 3604
Standard Ignition
2014 Dodge Journey Vacuum Pump 6 Cyl 3.6L Standard Ignition

P311-15F8C44    VCP146  New

010261721 , EC1429 , 4581486AB

Qty:
249.98
Standard Ignition Vacuum Pump
  • Vacuum Pump
  • Product Attributes:
    • Hardware Included: No
    • Hose Connector Quantity: 1
    • Hose Size - Inches: 3/8"
    • Notes: Vacuum
  • Direct-fit OE replacement ensures proper fit, form, and function, which leads to a trouble-free installation. High-quality O-rings and seals prevent leaks and maintain proper vacuum pressure. Undergoes 100% pressure testing to prevent leaks and ensure OE-matching performance. As a global manufacturer, we maintain complete quality control throughout the manufacturing process.
Brand: Standard Ignition
Additional Fitment Information:
Vehicle Block Engine CID CC
2014 - Dodge Journey V 6 Cyl 3.6L 220 3605
Standard Ignition
2014 Dodge Dart Vacuum Pump 4 Cyl 1.4L Standard Ignition

P311-532FA0B    VCP147  New

4892641AA , EC1430 , 4892641AB , 4892641AC

Qty:
337.63
Standard Ignition Vacuum Pump
  • Vacuum Pump
  • Product Attributes:
    • Hardware Included: No
    • Hose Connector Quantity: 1
    • Hose Size - Inches: 5/16"
    • Notes: Vacuum
  • Direct-fit OE replacement ensures proper fit, form, and function, which leads to a trouble-free installation. High-quality O-rings and seals prevent leaks and maintain proper vacuum pressure. Undergoes 100% pressure testing to prevent leaks and ensure OE-matching performance. As a global manufacturer, we maintain complete quality control throughout the manufacturing process.
Brand: Standard Ignition
Additional Fitment Information:
Vehicle Block Engine CID CC
2014 - Dodge Dart L 4 Cyl 1.4L 83 1368
Mopar
2006 Dodge Sprinter 2500 Vacuum Pump Mopar

P311-01B1A56    W0133-2280012  New

Qty:
446.76
Mopar Vacuum Pump
  • 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.
Brand: Mopar
Additional Fitment Information:
Vehicle
2006 - Dodge Sprinter 2500
Cardone
1999 Dodge Ram 2500 Vacuum Pump 6 Cyl 5.9L Cardone - Vacuum Pump

P311-0EB80DD    90-1309  New

5011796AA , 5019734AA

Qty:
319.00
Cardone Vacuum Pump
  • Vacuum Pump
  • Product Attributes:
    • E-Waste: No
    • Features and Benefits:
      • Designed For Easy Installation
      • Engineered To Meet Or Exceed O.e.m.performance
      • Guaranteed Fit And Function
      • Units Are Tested 100% To Ensure They Are Leak-free And Meet Vacuum Performance Standards
    • First Application Year: 1998
    • Mounting Bracket Included: No
    • Product Condition: New
    • Pulley Included: No
  • CARDONE New Vacuum Pumps are backed by CARDONE Engineered Technology, which ensures that all CARDONE Select New Vacuum Pumps meet or exceed O.E. form, fit and function. CARDONE Technology is based on over 40 years of reverse-engineering expertise, where original design weaknesses are identified and corrected, resulting in premium-quality, brand-new parts you can rely on. All units adhere to strict S.A.E. specifications and are 100% tested to ensure reliable, long-lasting performance.
Brand: Cardone
Additional Fitment Information:
Vehicle Block Engine CID CC
1999 - Dodge Ram 2500 L 6 Cyl 5.9L 359 -
Cardone
1990 Dodge W350 Vacuum Pump 6 Cyl 5.9L Cardone - Vacuum Pump

P311-5C21133    64-1300  Remanufactured

4429103

Qty:
$5.40 101.96
Cardone Vacuum Pump
  • Vacuum Pump
  • Product Attributes:
    • E-Waste: No
    • Features and Benefits:
      • 100% Computer Testing Guarantees Reliable Performance
      • 100% New Check Valves, Diaphragms, O-rings And Seals Prevent Leaks And Ensure Proper Vacuum Required To Efficiently Run Vehicle Accessories
      • Designed For Easy Installation
      • Engineered To Meet Or Exceed O.e.m.performance
      • Guaranteed Fit And Function
    • First Application Year: 1989
    • Mounting Bracket Included: No
    • Product Condition: Remanufactured
    • Pulley Included: No
  • CARDONE Remanufactured Vacuum Pumps are engineered for quick installation and no comebacks. Each unit is engineered and tested to meet or exceed Original Equipment Manufacturer performance, providing you reliable performance, every time. Original design weaknesses are corrected to make a longer lasting part you and your vehicle can rely on.
Brand: Cardone
Additional Fitment Information:
Vehicle Fuel Type Block Engine CID CC
1990 - Dodge W350 DIESEL L 6 Cyl 5.9L 359 -
Cardone
1991 Dodge D350 Vacuum Pump 6 Cyl 5.9L Cardone - Vacuum Pump

P311-5C21133    64-1300  Remanufactured

4429103

Qty:
$5.40 101.96
Cardone Vacuum Pump
  • without Intercooler
  • Vacuum Pump
  • Product Attributes:
    • E-Waste: No
    • Features and Benefits:
      • 100% Computer Testing Guarantees Reliable Performance
      • 100% New Check Valves, Diaphragms, O-rings And Seals Prevent Leaks And Ensure Proper Vacuum Required To Efficiently Run Vehicle Accessories
      • Designed For Easy Installation
      • Engineered To Meet Or Exceed O.e.m.performance
      • Guaranteed Fit And Function
    • First Application Year: 1989
    • Mounting Bracket Included: No
    • Product Condition: Remanufactured
    • Pulley Included: No
  • CARDONE Remanufactured Vacuum Pumps are engineered for quick installation and no comebacks. Each unit is engineered and tested to meet or exceed Original Equipment Manufacturer performance, providing you reliable performance, every time. Original design weaknesses are corrected to make a longer lasting part you and your vehicle can rely on.
Brand: Cardone
Additional Fitment Information:
Vehicle Fuel Type Engine VIN Block Engine CID CC
1991 - Dodge D350 DIESEL 8 L 6 Cyl 5.9L 359 -
Cardone
1991 Dodge D350 Vacuum Pump 6 Cyl 5.9L Cardone - Vacuum Pump

P311-114D87A    64-1301  Remanufactured

4638765

Qty:
$15.30 341.87
Cardone Vacuum Pump
  • with Intercooler
  • Vacuum Pump
  • Product Attributes:
    • E-Waste: No
    • Features and Benefits:
      • 100% Computer Testing Guarantees Reliable Performance
      • 100% New Check Valves, Diaphragms, O-rings And Seals Prevent Leaks And Ensure Proper Vacuum Required To Efficiently Run Vehicle Accessories
      • Designed For Easy Installation
      • Engineered To Meet Or Exceed O.e.m.performance
      • Guaranteed Fit And Function
    • First Application Year: 1990
    • Mounting Bracket Included: No
    • Product Condition: Remanufactured
    • Pulley Included: No
  • CARDONE Remanufactured Vacuum Pumps are engineered for quick installation and no comebacks. Each unit is engineered and tested to meet or exceed Original Equipment Manufacturer performance, providing you reliable performance, every time. Original design weaknesses are corrected to make a longer lasting part you and your vehicle can rely on.
Brand: Cardone
Additional Fitment Information:
Vehicle Fuel Type Engine VIN Block Engine CID CC
1991 - Dodge D350 DIESEL C L 6 Cyl 5.9L 359 -
Cardone
1992 Dodge W250 Vacuum Pump 6 Cyl 5.9L Cardone - Vacuum Pump

P311-114D87A    64-1301  Remanufactured

4638765

Qty:
$15.30 341.87
Cardone Vacuum Pump
  • Vacuum Pump
  • Product Attributes:
    • E-Waste: No
    • Features and Benefits:
      • 100% Computer Testing Guarantees Reliable Performance
      • 100% New Check Valves, Diaphragms, O-rings And Seals Prevent Leaks And Ensure Proper Vacuum Required To Efficiently Run Vehicle Accessories
      • Designed For Easy Installation
      • Engineered To Meet Or Exceed O.e.m.performance
      • Guaranteed Fit And Function
    • First Application Year: 1990
    • Mounting Bracket Included: No
    • Product Condition: Remanufactured
    • Pulley Included: No
  • CARDONE Remanufactured Vacuum Pumps are engineered for quick installation and no comebacks. Each unit is engineered and tested to meet or exceed Original Equipment Manufacturer performance, providing you reliable performance, every time. Original design weaknesses are corrected to make a longer lasting part you and your vehicle can rely on.
Brand: Cardone
Additional Fitment Information:
Vehicle Fuel Type Block Engine CID CC
1992 - Dodge W250 DIESEL L 6 Cyl 5.9L 359 -
Cardone
1998 Dodge Ram 3500 Vacuum Pump 6 Cyl 5.9L Cardone - Vacuum Pump

P311-459109C    64-1309  Remanufactured

5019734AA

Qty:
$5.40 278.16
Cardone Vacuum Pump
  • Vacuum Pump
  • Product Attributes:
    • E-Waste: No
    • Features and Benefits:
      • 100% Computer Testing Guarantees Reliable Performance
      • 100% New Check Valves, Diaphragms, O-rings And Seals Prevent Leaks And Ensure Proper Vacuum Required To Efficiently Run Vehicle Accessories
      • Designed For Easy Installation
      • Engineered To Meet Or Exceed O.e.m.performance
      • Guaranteed Fit And Function
    • First Application Year: 1998
    • Mounting Bracket Included: No
    • Product Condition: Remanufactured
    • Pulley Included: No
  • CARDONE Remanufactured Vacuum Pumps are engineered for quick installation and no comebacks. Each unit is engineered and tested to meet or exceed Original Equipment Manufacturer performance, providing you reliable performance, every time. Original design weaknesses are corrected to make a longer lasting part you and your vehicle can rely on.
Brand: Cardone
Additional Fitment Information:
Vehicle Block Engine CID CC
1998 - Dodge Ram 3500 L 6 Cyl 5.9L 359 -
Cardone
2004 Dodge Ram 3500 Vacuum Pump 6 Cyl 5.9L Cardone - Vacuum Pump

P311-53AEF56    64-1509  Remanufactured

53032373AB , F81Z2A451AD , 53032373AC , 4C3Z2A451BA , 7C3Z2A451B , F81Z2A451BA , 6C3Z2A451A , 4C3Z2B925AB , 4C3Z2B925AA , YC3Z2B925AA

Qty:
$5.40 76.87
Cardone Vacuum Pump
  • with Speed Control Vacuum Pump
  • Vacuum Pump
  • Product Attributes:
    • E-Waste: No
    • Features and Benefits:
      • 100% Computer Testing Guarantees Reliable Performance
      • 100% New Check Valves, Diaphragms, O-rings And Seals Prevent Leaks And Ensure Proper Vacuum Required To Efficiently Run Vehicle Accessories
      • Designed For Easy Installation
      • Engineered To Meet Or Exceed O.e.m.performance
      • Guaranteed Fit And Function
    • First Application Year: 1999
    • Mounting Bracket Included: No
    • Product Condition: Remanufactured
    • Pulley Included: No
  • CARDONE Remanufactured Vacuum Pumps are engineered for quick installation and no comebacks. Each unit is engineered and tested to meet or exceed Original Equipment Manufacturer performance, providing you reliable performance, every time. Original design weaknesses are corrected to make a longer lasting part you and your vehicle can rely on.
Brand: Cardone
Additional Fitment Information:
Vehicle Block Engine CID CC
2004 - Dodge Ram 3500 L 6 Cyl 5.9L 359 -
Cardone
1997 Dodge Ram 3500 Vacuum Pump 6 Cyl 5.9L Cardone - Vacuum Pump

P311-5CA138A    64-1303  Remanufactured

4897243AA , 104897243AA , 4874365

Qty:
272.58
Cardone Vacuum Pump
  • with Intercooler
  • Vacuum Pump
  • Product Attributes:
    • E-Waste: No
    • Features and Benefits:
      • 100% Computer Testing Guarantees Reliable Performance
      • 100% New Check Valves, Diaphragms, O-rings And Seals Prevent Leaks And Ensure Proper Vacuum Required To Efficiently Run Vehicle Accessories
      • Designed For Easy Installation
      • Engineered To Meet Or Exceed O.e.m.performance
      • Guaranteed Fit And Function
    • First Application Year: 1997
    • Mounting Bracket Included: No
    • Product Condition: Remanufactured
    • Pulley Included: No
  • CARDONE Remanufactured Vacuum Pumps are engineered for quick installation and no comebacks. Each unit is engineered and tested to meet or exceed Original Equipment Manufacturer performance, providing you reliable performance, every time. Original design weaknesses are corrected to make a longer lasting part you and your vehicle can rely on.
Brand: Cardone
Additional Fitment Information:
Vehicle Block Engine CID CC
1997 - Dodge Ram 3500 L 6 Cyl 5.9L 359 -
Standard Ignition
2003 Dodge Ram 2500 Vacuum Pump 6 Cyl 5.9L Standard Ignition

P311-0DCADE0    VCP112  New

4C3Z2A451BA , AP63433 , 904-214 , 7V1006 , 53032373AA , BRPV7 , 4C3Z2B925AB , 57-8508 , 6C3Z2A451BA , VP16 , F81Z2A451BA , 4C3Z 2A451 BA , 6C3Z-2A451-A , 64-1509 , 600-2973 , 53032373AC , VDV23 , 53032373AB , VP8 , F81Z2A451AA

Qty:
101.25
Standard Ignition Vacuum Pump
  • Vacuum Pump
  • ; Electronic
  • Product Attributes:
    • Hose Connector Quantity: 2
    • Hose Size - Inches: 1/4, 5/16"
  • Each Vacuum Pump is a direct-fit OE replacement that ensures ease of installation. High-quality materials withstand extreme conditions. Undergoes extensive testing to ensure reliability. As a global manufacturer of automotive aftermarket products, we maintain complete quality control throughout the manufacturing process.
Brand: Standard Ignition
Additional Fitment Information:
Vehicle Block Engine CID CC
2003 - Dodge Ram 2500 L 6 Cyl 5.9L 359 -
Standard Ignition
2003 Dodge Ram 2500 Vacuum Pump 6 Cyl 5.9L Standard Ignition

P311-334E102    VCP142  New

5102084AA , EC1425 , 64-1027

Qty:
1,131.72
Standard Ignition Vacuum Pump
  • Vacuum Pump
  • ; Mechanical
  • Product Attributes:
    • Hardware Included: No
    • Hose Connector Quantity: 1
    • Hose Size - Inches: 3/8"
    • Notes: Vacuum
  • Direct-fit OE replacement properly restores pressure to ensure efficient running of vehicle accessories. High-quality O-rings and seals prevent leaks and maintain proper vacuum pressure. Precision-cut vacuum pump pulley shaft ensures exact OE dimensions for proper fit and easy installation. Undergoes 100% pressure testing to prevent leaks and ensure OE-matching performance. As a global manufacturer, we maintain complete quality control throughout the manufacturing process.
Brand: Standard Ignition
Additional Fitment Information:
Vehicle Block Engine CID CC
2003 - Dodge Ram 2500 L 6 Cyl 5.9L 359 -
Standard Ignition
2003 Dodge Sprinter 2500 Vacuum Pump Standard Ignition

P311-18D829A    VCP177  New

5117674AA , EC1460 , 6112300265 , 904-848

Qty:
258.13
Standard Ignition Vacuum Pump
  • Vacuum Pump
  • ; Genuine Intermotor Quality
  • Product Attributes:
    • Hardware Included: No
  • Direct-fit OE replacement ensures proper fit, form, and function, which leads to a trouble-free installation. High-quality O-rings and seals prevent leaks and maintain proper vacuum pressure. Machine-cut pulley shaft ensures OE-matching dimensions for precise fit and ease of installation. Undergoes 100% pressure testing to prevent leaks and ensure OE-matching performance.
Brand: Standard Ignition
Additional Fitment Information:
Vehicle
2003 - Dodge Sprinter 2500

Latest Car Advice

CarJunky AutoAdvice

2001 dodge diesel ,heater fan and control problem

Showing 3 out of 4 Posts | Show 1 Hidden Posts
Question From bill15080 on 2001 dodge diesel ,heater fan and control problem

2001 dodge diesel heater fan runs but no air circulates to desired areas, acts like air can't get through the fan to get distributed to windshield or feet or anywhere

Response From Tom Greenleaf

Question first - Do you hear it trying to change airflow direction mode at all?

My WAG is you have debris from a rodent that plugged up the heater box, squirrel cage of blower type issue??

T

Response From bill15080

IT IS WORKING TODAY, INTERMITTENT, SO I DON'T THINK THE DOORS ARE BROKEN..VACUUM ISSUE POSSIBLY...WAITING FOR IT TO SCREW UP AGAIN SO I CAN DISCONNECT THE VACUUM LINE AND RECONNECT TO SEE IF IT WORKS THEN>>?? MAYBE A CHECK VALVE IN VACUUM SYSTEM? I HAVE A WORKING VACUUM PUMP ON THE POWERSTEERING PUMP...I CAN FEEL THE VACUUM...ANY IDEA'S WOULD BE APPRECIATED TY BILL NO... NO RODENTS YET(:>))

Response From Tom Greenleaf Top Rated Answer

Intermittent can be tough. Mopars not my strongest suit but if doors are vacuum controlled and could be most have a reservoir of some type probably plastic but may not with a mechanical vacuum pump set up. No matter - look for and at all vacuum hose, many are first rubber to plastic line that at a glance looks like a wire.

If vacuum controlled and a split in something it would default to near always just defrost ducts with a total lack of supply. Follow any line that's vacuum going into heater/A/C box or thru firewall. Those do get brittle or burn, rub like things can along the way and some azzhole engineers place the dang hoses near dipsticks and they get broken easily doing something else

If electrically actuated doors I don't find broken actuators commonly intermittent but you may hear a stripped nylon gear trying to work and can't, then work for a while?

T

1993 dodge dakota acceleration problems

Showing 4 out of 54 Posts | Show 50 Hidden Posts
Question From individualizedrepair on 1993 dodge dakota acceleration problems

I have a 1993 dodge dakota v6 that I am having some issues with. Ever since it got cold out acceleration is sporadic and at times seems not to want to accelerate at all. It feels to me when this happens like it is not getting fuel. I replaced the fuel pump and filter which did not solve anything. I have cleaned the throttle body and replace the gasket also. Spark plugs and wires seem fine even though it has been a while since they have been changed. The truck runs great when idling and without being under load will rev up steady all the way. Seems like once the truck warms up the problem gets better but it is still very sporadic and happens at random times. When this happens if I floor the truck it will come out of the bad acceleration and accelerate fine until I let off the gas and rpms go back down. I am wondering if it could be the crankshaft or throttle positioning sensor but I would like some input before doing anything else to the truck since I am not exactly a mechanic. Thanks in advance for your help!

Response From Discretesignals

Check engine light on? If so, do the key dance with the ignition switch. (ON, OFF, ON, OFF, ON) This will cause the engine computer to display trouble codes by flashing the check engine light. Write down the numbers.

Response From individualizedrepair

it displays 12-14-14 checked voltage to the uh whatever it is middle and third post both read around 5.5v. check engine light is not on though

Response From Discretesignals

14 code is a MAP sensor high or low voltage code. Beware this code can set if you unplug the MAP sensor with the engine running. To be sure this code wasn't set by someone or yourself unplugging the MAP sensor, disconnect the battery for 10 secs to erase codes, and then see if the code returns.

If it does, you'll need to check the MAP sensor signal voltage using your volt meter.

Response From individualizedrepair

This code came on after disconnecting the battery for fuel pump replacing. It was not disconnected while the engine was running. The voltage is about 5v on both terminals which through research is what it should be at. I am not sure why it is showing this code but would a bad MAP sensor cause this kind of issue anyway?

Response From Discretesignals

Did you make these electrical checks with the sensor connector plugged in? You need to back probe the connector using a T pin or something you can connect your meter to. Make all measurements with your volt meter negative lead connected to battery negative. Do not short the 5 volt power supply to ground.

Violet/white wire should have 5 volts (power supply for MAP sensor)
Black/light blue wire should have less than 0.1 volts. (sensor ground)
Dark green/red will have between .5-4.5 volts on it depending on manifold vacuum. With the engine running you should see around 1.5 volts. Under hard acceleration the voltage should be about 4 volts.

The MAP sensor is critical to the running of the engine and is used to by the PCM to calculate engine load for fueling and timing. It also is used by the TCM for transmission operation.

Response From individualizedrepair

back probed using t-pin with engine running as suggested. Middle I get a solid 5 on violet/white and 1.7 on green/red when idling. No voltage on black/blue. This is going back to negative battery terminal for negative. When I rev the engine up the map voltage on green/red actually goes down. From .2 to 1.2 somewhere under hard acceleration. Does this mean I have a bad MAP sensor?

Response From individualizedrepair

The map sensor common voltage comes from the pcm so if i am getting 5v to the common on the map sensor that means the pcm is feeding the map sensor properly correct?

Response From Discretesignals

The voltage on the signal wire should go up as manifold vacuum goes down. With the key on engine off the voltage from the MAP should be around 4 volts on the signal. The PCM supplies 5 volts to power the sensor. The PCM also sends 5 volts down the signal wire.

Connect a vacuum gauge to manifold vacuum and monitor engine vacuum while monitoring the MAP sensor voltage. You'll understand the correlation. If your vacuum gauge shows low vacuum under hard acceleration, but the MAP's voltage goes down instead of up, I'd say something is up with the MAP sensor. What was the voltage on the ground wire? It has to be less than or equal to 0.1 volts. That will tell you if the MAP sensor has a good ground.

Response From individualizedrepair

I do not have a vacuum gauge but under hard acceleration the voltage does go down. I understand the corralation now that you explained it. Should i chrck input to signal wire from map sensor or should it be good since common is at 5v? Ground wire has 0.0 volts so the ground should be good. Map sensor is pretty cheap so you think this could possibly bethe issue?

Response From Tom Greenleaf

Get a vacuum gauge - still good info with the things. Handy as all get out is this type.........
http://ts1.mm.bing.net/th?id=H.4634455629038983&pid=1.9&m=&w=300&h=300&p=0
Pumps to make vacuum for testing and reads vacuum both. Not expensive and should come with a "T" so if inline to actual vacuum the item is still operating you are just watching what it gets - cool tool,


T

Response From individualizedrepair

Ok got a vacuum gauge for testing. I get about .5 to 1 hg during idle and when rpm's go up the vacuum goes up. I get about 19 hg at 4000 rpm. My voltage from map sensor at 4000rpm is around 1v usually. I get about 1.7v from the map sensor with engine idling. Does this mean the map sensor is bad and should be replaced? Remember I was getting error code 14 which is map sensor voltage high/low also...

Response From Hammer Time

You have to be reading that from the wrong place. You should have your highest reading at idle.

A healthy engine shouls be seeing 16-18" at idle and as you slowly increase the RPMs you shouldn't drop more that an inch or two at 2000RPM.

Response From individualizedrepair

I am reading it from the only vacuum hose going to the throttle body, is this the right place or where should I be reading it from?

Response From Hammer Time

You have to be reading from behind the throttle plate to get full manifold vacuum. It sound like you are reading in front of the throttle plate and you won't get a reading there until the throttle is opened.

Response From individualizedrepair

ok, reading from back of throttle body. get 16hg when idling and 18hg when at 2000rpm. Not sure why the vacuum is going up?

Response From individualizedrepair

so it would seem like my vacuum readings are operating correctly under normal parked conditions then? I do not get any jumping or anything else with it and the map sensor code 14 was thrown from the vehicle. Just trying to figure out if the map sensor is bad or not I suppose.

Response From Discretesignals

Did you get a hand held vacuum pump/gauge like in the picture above or just a gauge?

Response From individualizedrepair

just a gauge. I took off the map sensor and checked voltage while manually sucking. 6hg is the highest I can get this way and hold steady. At 6 hg it is reasing 3.3v solid

Response From Discretesignals

You would have more control with a pump than your mouth, but at 6 inhg 3.3 volts is about right. Do you understand the correlation between the voltage and pressure the sensor senses? Lower vacuum equals higher voltage and higher vacuum equals lower voltage. You really want to test the full swing of the sensor to be sure it is operating properly.

If the sensor's voltage properly corresponds to the vacuum you apply to it and doesn't drop out or go high voltage, the sensor is good. From there you really need to monitor data stream information using an enhanced scan tool to see what the engine computer is seeing from the sensor.


I'm starting to wonder if something else is causing this code to set. 16 inches of vacuum at idle isn't all that great. Is the gauge steady, bouncing around, or slowly moving around at 16 inches during idle? Could have a vacuum leak or an ignition timing issue.

Response From individualizedrepair Top Rated Answer

the gauge does not bounce at all during idling at around 16hg. I got a vacuum pump and everything seems about right, I got as follows

4.5-4.6 at 0hg
3.8 at 6hg
3.3 at 9hg
2.5 at 14hg
2.2 at 16hg
1.7 at 18hg
1.4 at 20hg

So it seems to me like the map sensor is working right then so something else has to be causing it to throw that code then. I checked all of the lines that I could see and they do not seem to have any issues. I got some new fitting when I went to the auto store and replaced a bunch of them. It is just weird how this only happens when rpms are down around 2000 usually and other times it is fine. Plus it acts up more in the cold than the heat. It is a 93 so I did not think they could do advance diagnostics on it?

Response From Discretesignals

Have you tested your TPS sensor using your volt meter. TPS is almost just like the MAP sensor. It has 5 volt reference, signal, and ground. You connect your meter to the signal circuit and meter ground lead to battery neg. Very slowly open the throttle while watching your meter. Should be around .5 volt closed to 4.5v wide open without any drop outs in between.

Orange/dark blue signal .5-4.5v
violet/white 5 volt reference 5v
black/light blue ground less than or equal to 0.1v

Response From individualizedrepair

no I have not checked it, is that the sensor by the map sensor off to the right?

Response From Discretesignals

It is screwed onto the side of the throttle body. The throttle plate shaft rotates the wiper inside the sensor.

&imagekey=1112785-0&width=450

Response From individualizedrepair

Ok, I will get it checked out tomorrow over lunch. I cannot run the truck anymore this late since the kids are in bed now. I thank you for all of your help with this and I will post again as soon as a check it out. Again thank you for all your help.

Response From Discretesignals

No problem. It is hard to diagnose drive ability issues over the internet, but you do know the MAP sensor is working. Just don't understand why it set that code unless it was unplugged or had some type of intermittent circuit issue. I've seen MAP sensor codes set when there is a rationality issue because of the engine running really bad. I don't care for the 16 inches of vacuum at idle thing. It may get to the point that you will need to bring it to a shop that does drive-ability to figure it out. It might require scan tool data information to be read and other testing that requires more advanced diagnostic procedures and tooling.

Another thing is if this engine has a bunch of miles on it, it might be worn out. Worn out rings, timing chains, and other parts that affect manifold pressure will cause all kind of issues with fueling and ignition controls. The PCM relies a whole lot on manifold pressure for making critical calculations.

Response From individualizedrepair

yes atleast I now know that the map sensor works good. I do not have any idea why it would throw this code. The battery was reconnected after fuel pump replacement and it is the only code i get: 12, 14, 14 So I am not sure. the engine sounds great besides being a little loud with exhaust. it idles fine and is good sounding when revved up. I will check out the tps tomorrow and if that does not work I will get it to a mechanic and go from there, I just hate the ridiculous cost and inconvenience of taking it to someone when I am mechanical just not electrical system minded. The engine has about 160k miles on it and does burn/loose some oil so there may be some issue there. Too many electronics why can they just not have a damn engine nice and simple like it used to be, like the air compressor and generator engines I work on? Nice and simple, that is how I like it!

Response From Discretesignals

Because big brother wants cars with reduced emissions that use less fuel, so the only way to accomplish that is to have a computer control everything.

Believe me, that system is simple in how it works compared to more modern systems. That system is actually easier to work on than computer control carburetors. This new stuff with VVTi, direct injection, 7 speed transmissions would blow your mind and it just keeps getting more and more complex. Not only are the ways fuel and emissions controls more complex in nature, but also how the software and data transmission between modules is constantly evolving. Mechanics/technicians are now becoming more like IT specialists.

Response From individualizedrepair

checked tps and I get 5v on common. On Orange I get .7v at closed throttle and 3.8v at wide open. Is this within normal range for the sensor?

Response From Discretesignals

According to service data the TPS voltage should be around 1 volt at idle and 3.5 volts at wide open throttle. It is important that you don't have any drop outs as you slowly open the throttle. Digital volt meters aren't really great for finding drop outs because their sampling rate is too slow. You really need something that can graph the signal such as a graphing multimeter or lab scope.

Looks like you may need to find someone with an enhanced scan tool or a DRB to watch data stream information. Even though it is an old truck they had datastream capabilities and bidirectional control on certain actuators.

You can test other sensors such as the engine coolant temperature sensor and the O2 sensor, but being able to look at all inputs and outputs at the same time would be so much easier.

Response From individualizedrepair

Ok, I am taking it in on monday to a repair shop. Talked to them and they said they cannot hook up to computer. I do not think anyone in town has the old school testing stations they used to run. I will let you know what I find out though, thank you very much for all the help!

Response From nickwarner



The big box analyzers are gone the way of the dodo, but a shop that doesn't even have an OBD 1 hookup to this is not equipped to do real driveability diagnostics. Anyone with a quality scan tool has these hookups. If they do not have the requisite tool, they no likely do not have the knowledge to diagnose this right, they will just throw parts at it until your wallet is paper thin. Don't shop the craigslist idiots and cheap shops. Your money is best spent with someone who knows what they are talking about in the long run.

Response From individualizedrepair

I think almost all shops now carry the obd2 instead from what I can gather? I am not sure about this but I will definitely ask before I drop it off tomorrow morning. I do know that they said something about not being able to hook it up to a scan tool when I originally talked to them and told them is was a 1993. If they do not have one I will find someone who does. Thanks for the info!

Response From Hammer Time

I think almost all shops now carry the obd2 instead from what I can gather?


Apparently you aren't listening to anything you have been told. There is no competent shop operating anywhere that doesn't have OBD1 capability at least at the ownership level. Hell, I personally own 3 of them. They are cheap now and no longer require updating.

We are all professionally techs either currently working in the business or recently retired.

Now, you may not find a lot of shops that are interested in working on your car so they may tell you anything to make you go away but if they say they don't have OBD1 equipment, drive away.

Response From individualizedrepair

I listened and understood what I was told but shops around here are probably not too interested in working on older model cars/trucks so they tell you all this so they have to charge you a large and timely diagnostic fee for doing nothing more than a driving scan. I did not know anything about scan tools and now I know a lot more and I appreciate the help and knowledge I need to have my truck worked on by someone who half knows what the hell is going on.

Response From Hammer Time

I need to have my truck worked on by someone who half knows what the hell is going on.

If he tells you right up front that they don't have OBD1 equipment, then you are at the wrong shop. Of course they are going to charge you diagnostics. OBD1 requires a lot more actual diagnostics than OBD2 does. This isn't like the free code read you get from parts stores. This guy has to actually know what he is doing.

Response From individualizedrepair

I took the truck to a shop that has obd1 scanner but they said unless it is throwing a code or the check engine light was on it is useless? Is this true? They checked out the truck and said it was plugs, wires, cap and rotor. I replaced it all along with pcv valve for complete tune-up. Truck still does the same thing. Can the obd1 scanner be used for driving diagnostic or what kind of shop do I need to be taking it to?

Response From Hammer Time

No, that's not true. He has access to an entire list of sensor data that can be analyzed to look for an issue, assuming the problem is present at the time. You need a real driveabilty tech to be able to look for this stuff. If you're just hitting the chain stores like Firestone, Good year, brake shops, etc, they are not the caliber of people that can do this.

Response From individualizedrepair

Ok so I have a little more information. I usually only drive around town and do not get above 40mph most times in town. When I went out of town this week I got the truck up to around 60 and it seems like when it cuts out there is an engine/transmission thump when it stumbles and rpm's drop. This made me think crankshaft position sensor which I replaced with no help to the symptoms. Seems like the cps being out would not give these symptoms anyway (obviously why I am not a mechanic). Any ideas with the trans/engine sound and symptoms if this could change the diagnosis?

Response From Discretesignals

One thing that those engines were known for was a leaking plenum pan gasket when they get old. The engine would suck oil up through the bottom of the intake. This would cause the engine to knock under acceleration, because the oil increases the compression, would cause the engine to burn excessive oil, and would cause a vacuum leak resulting in possible rough idle. It may be exacerbated when the engine is cold because things tend to shrink which make more of a leak.

With the air cleaner and engine off, open the throttle all the way and look at the floor of the intake with a flashlight. If you see oil laying down there, it is a good bet the gasket is done.

You can also disable and plug off the PCV system (vent and valve). Then connect your vacuum gauge to the dipstick tube. If the gasket is leaking, it will create vacuum in the crankcase while it is idling. That is if the crankcase is sealed, of course.



intake plenum pan gasket at top:

&imagekey=125632-0&width=450

Response From individualizedrepair

I took a look down past the throttle and it is all a caramel/oil color. There is not standing oil and does not appear to have oil currently in it. Will it be better if I take a look right after running the engine? I have been home for about 3 hours now, just wondering if that would make a difference or if the oil would stay there at the bottom.

Response From Discretesignals

It will stay at the bottom. The caramel color may be baked on oil also.

Response From Hammer Time

Any shop worth a damn has an OBD1 scan tool. If they don't have the capability, then you need a different shop. This isn't exotic equipment for them to own.

Response From Hammer Time

Not having a pump kinds defeats the intent of testing the sensor.

Response From individualizedrepair

ok, going to get one right now.

Response From individualizedrepair

I do not know, obviously I have not a clue what I am doing buck I am usually mechanical, just not good with electronics on engines. What is the best way to test this issue? basically the truck cuts in and out at times when accelerating almost feels like it is running out of gas. I accelerate hard and it comes out of it usually until rpms and acceleration go back down then it starts to sputter again. Seems like it does worse when it is cold and gets better when warming up.

Response From individualizedrepair

just gauge. I took it off and tested with ignition on and sucked with pressure. At 6hg it is at 3.3v. That is the most I can get it manually. Should I go get a vacuum pump also?

Response From Discretesignals

Should correspond like this with the voltage signal from your MAP sensor.





Remember that at 4000rpm you will probably see high vacuum readings if you slowly bring the rpm to that or hold that rpm in park. The engine isn't under any load in park. If you snap the throttle in park or you have the vehicle in gear and you accelerate, you will see a drop in vacuum.

Response From individualizedrepair

busted a t fitting, going to get a replacement, ill let you know and thank you for the help

Response From individualizedrepair

i'm looking for a vacuum gauge similar to what you showed me and I am having a hard time finding one. Any suggestions on where to get one at? Voltage at high rpm about 4000rpm is 1.0v to map sensor so I am either not getting enough vacuum or the sensor is bad...

Response From Hammer Time

They are readily available at most tool suppliers in varying quality.


http://www.tooltopia.com/mityvac-mv8000.aspx

http://www.amazon.com/MHB-LB122-Hand-Vacuum-Pump/dp/B003B3WC3Q

http://www.harborfreight.com/brake-bleeder-and-vacuum-pump-kit-69328.html

http://www.autozone.com/autozone/accessories/OEM-Vacuum-pump-and-gauge-tester-includes-24-in-tube/_/N-25jr?itemIdentifier=2080_0_0_

Response From individualizedrepair

Ok thanks, I'll pick one up!

Response From individualizedrepair

Ill grab one and let yoy know what i come up with thankd

Response From individualizedrepair

So I should take these readings with the engine running on the back side of the connector correct? Before I looked at a tutorial and it said to take the common when off and unplugged and just backprobe the other connection while engine was off and ignition was on. Got about 5v for both readings. Is this a false way to do it? Both should be taken when engine is on and it is plugged in and backprobe both correct?

How to bleed a clutch slave cylinder that has no bleeder valve?

Showing 3 out of 9 Posts | Show 6 Hidden Posts
Question From Mr.scotty on How to bleed a clutch slave cylinder that has no bleeder valve?

In all the years I've been repairing vehicles I never seen this before.
I'm repairing a 96 Dodge dakota 2.5 2wd 5speed that needs a slave cylinder.
I bought the slave cylinder and saw it had no bleeder valve, and the old one doesn't either.
How did they bleed this to began with?
Any idea's on how i can bleed this thing?

Thanks

Response From Discretesignals

Those are a PITA. What I do is take the master, reservoir, and line off the vehicle. On a bench have someone keep the reservoir full of brake fluid. Next, bench bleed the master with the line attached. Make sure the master is angled so no air can get trapped. Then take the slave and tilt it, so you can pour fluid into it. Once full, connect it to the line. Put the whole thing as one unit back onto the vehicle.

Response From Mr.scotty

Ok.., Thats a good idea.
I ended up doing this:
I had someone keep the clutch master cylinder full of fluid while i was uder the truck pumping the slave cylinder by hand, i removed the little shaft that comes out of it and put a 3/8x5" extension in there and put the other end on the ground and just kept pushing it down back and forth untill all the bubbles stoped coming out the the fluid reservoir.
The clutch pedel feels like butter now and it's nice and high.
So i didn't need to remove it from the vehicle, so atleast that saved me a little time.

Thanks for the reply!

Response From Tom Greenleaf

This sh*t can suk. Some just don't cooperate without tons of bad language and keep children away! With some used a vacuum pump to alter gravity!

T

Response From Mr.scotty

I hear ya Tom.
Why in the world would someone ever have the bright idea to design something wihtout a bleeder vavle on it?
This is the only time I've ever seen this.., I've never saw chevy or ford do anything like this.

The way i did it worked great though, Guess it's just another "trick of the trade" huh.

Response From Blulakr



This is the only time I've ever seen this.., I've never saw chevy or ford do anything like this.




Ford has done it for years.

Response From Hammer Time

You guys need to watch the dates on the thread. This one is months old and really shouldn't be commented on any longer.

Response From Tom Greenleaf

No problem Mr. Scotty. Put the vehicle on its roof and you are all set!

Tom

Response From pooby92 Top Rated Answer

I had to bleed the clutch master on a Shelby Mustang GT (newer style. 2007 I think) that had no bleeder. I used a rubber stopper (like a drain plug) that fit tight in the top of the master. I drilled a hole in the middle of the stopper and stuck a small metal tube in it.

With the stopper pressed into the master opening, I attached a vacuum pump to the metal tube in the stopper. I put it under 20 in. of vacuum and held it for a minute. I repeated this two more times.

Worked perfect.

1996 dodge intrepid map sensor code

Showing 2 out of 4 Posts | Show 2 Hidden Posts
Question From bmac on 1996 dodge intrepid map sensor code

I recently replaced a cylinder head on a 96 intrepid and a week later the valve spring broke causing alot of other problems. I replaced the head AGAIN and it was fine for about 3 days. Now its suddenly running bad and has a code for MAP sensor (no change from start to run). Map sensor is not the problem and I have vacuum and power at it. I would greatly appreciate any help.

Response From steve01832 Top Rated Answer

With a multimeter set to the 20 volts scale backprobe map sensor connector terminals ground and signal return. Turn key on and observe reading. Watch meter as you start the engine. The voltage should have a dramatic change. If no change, leave meter connected and turn key on engine off. Pump map sensor with a vacuum pump. As you apply vacuum map readings should drop off. If the reading doesn't change, replace sensor. If the sensor reads ok check wiring to sensor from PCM. If all checks out ok perform a compression test on all 6 cylinders and install a vacuum guage. Any compression problems will affect vacuum. Map sensor will pick these vacuum problems up and if they are bad enough, set a code. Good luck and let us know how it's going.

Steve

Response From bmac

Well, I found the problem with the Intrepid. Oddly enough the problem was a broken exhaust valve spring! Apparently Chrysler is having alot of problems with them on their remanufactured heads. Thanks again for replying to my problem and again I'm glad there's people like you out here to help me when I get in a jam.

Response From bmac

Thanks! I will try it next week. I was way too busy to even open the hood on it today. I run a 16 bay repair shop by myself and it gets a little crazy sometimes. Its great to know someone like you is out there to help. Thanks again!!!

Odd Sound Coming from TXV or Evaporator

Showing 2 out of 11 Posts | Show 9 Hidden Posts
Question From dw8 on Odd Sound Coming from TXV or Evaporator

1994 Dodge Caravan SE, 3.3L, 98,000

I'm getting an odd sound in the passenger compartment (which appears to originate from the center dash area) ONLY when the A/C is on and the car is accelerating.
The sound can not be heard in the engine compartment.
At idle the sound is NOT heard NOR does the sound occur with just heat or blower only on.
I'm getting between 42 and 52 out of the A/C depending on ambient.
This has been going on for some time.
Last time I put gauges on they meet specs.

Before I recover the Refigerant, Vacuum and Recharge, anyone have any ideas what is causing this and whether a recharge will solve the problem?

Response From Double J

Just saw your post in the other thread ....

This bulletin applies if yours has the Expansion Valve with part # 4677203
But as of 3/94 production date, they changed to the new part # 4766334
If yours has that then this doesn't apply....

Response From dw8

Thanks for Reply:

I do have part # 4677203 per the TSB.
Interesting that it worked fine for a number of years but last 3 or 4 is when the sound started.
I also have the same problem I replied to with the gentleman with the 2007 Grand Carava-- that is -- the AC cuts out from the center vents and is redirected to the defost vents when extra power needed (climbing a hill).
I've tested the check value (canister) -- mine attached to brake booster -- and holds 8 Hg of vacuum as chec k value designed.
Have NOT set up a test jig to try and check all door accurators, but all buttons appear to function as designed and direct air accordingly.

Question:
1) Think the two issues are related or independent?
2) Know whether Dodge built in some kind of AC cutout in the PCM when extra power needed and air redirection is just Normal?

Thanks
David

Response From Tom Greenleaf

Quote ">>
I also have the same problem I replied to with the gentleman with the 2007 Grand Carava-- that is -- the AC cuts out from the center vents and is redirected to the defost vents when extra power needed (climbing a hill)."


NO! That's not for extra power it's from loss of vacuum somewhere maybe not where you tested. Engines under load have no vacuum to supply so it's stored in a ball or can with a check valve in line for hold items where they were when no vacuum exists like asking for full or more power. For that they might (or some will add) a cut out for compressor under WOT = wide open throttle situations for max power.


Just to clarify just that,


T

Response From dw8

Mr. Greenleaf: Thanks for staying with me on this.


Engines under load have no vacuum
Agree that at idle max vac, as load increases vac decreases.

From what I can see the brake booster is the can as check valve connects directly to it.
From check value vac supply runs throught firewall to whereever -- most probably the A/C heater control assembly.

Unless the A/C heater control assembly is leaking somehow, you would think that if a button is pushed
which should redirect the vacuum to whatever door actuator, then climbing a hill would not cause air to be redirected to defrost.
ONly other things I can think of are:
1) the door is Not closing off completely and the air is bypassing it and consequently getting a redirect to defrost..
But if this is the case air should be coming out of defrost at all times.
2) When climbing the vacuum is dropping so low, that this is causing the blend door to close or close partially which
would then cause the air to be redirected -- defrost in this case.

Since the check values tests OK -- put a hand vacuum pump on it at 8Hg for 10 minutes and no leak down -- any idea how to troubleshoot this?

Response From Tom Greenleaf

In a hurry somewhat - sorry. Vacuum booster will be on its own for all safety reasons. Other vacuum controlled anything (includes many mode control actuators for heat, A/C vents or blend controls on some vehicles) uses the storage ball or can. Ball I think on this AND a check valve. You know it works if engine is off the next day or even 5 minutes it should change modes with ignition on and engine off at least once. If not it leaks somewhere. Most common is under hood plastic line looks like wire. At first it has to have a crack or maybe melted spot till you get nothing than it will only put air out defrost as the default mode when things fail.


Your reading of just 8Hg (inches of mercury) is low. Engines spike vacuum upon deceleration, idle should be around 18+/-. While driving along it will be all over the place with assorted loads and hold the max it got in that storage can/ball.


This being now 21 years old is more likely to use more vacuum things that very new. Any leaks to the source intake manifold actual pressure will lower your reading but also run like crap but it isn't bad enough.


This could also be what you are hearing! Listen for it. No telling what a split vacuum something might do for a sound? Age and all still more likely under the hood.


Hard to think a TSB this late just decided to show up now but could have.


Back to work for me. Go listen for a leak in a line going thru firewall. Wiggle test might really show you which one. It's ok if you find plastic line to razor cut and splice in windshield washer size common hose over the bad part. Wire cutters can pinch plastic vacuum line and seal it closed. Good luck. I think that's your noise,


T


T

Response From dw8


Other vacuum controlled anything (includes many mode control actuators for heat, A/C vents or blend controls on some vehicles) uses the storage ball or can. Ball I think on this AND a check valve.

Only check I've found in engine area is the one on the brake booster.
Will have to remove center console to see if another one on same line in passenger compartment.

FWIW There are two lines in the engine compartment.
The vac supply going from -- brake booster > check value > firewall > inside cab (assume to AC heat control assembly)
Line from cab > firewall > Heat Control Value (this value turns off the coolant running to the heater core).


You know it works if engine is off the next day or even 5 minutes it should change modes with ignition on and engine off at least once. If not it leaks somewhere.
Great TIP. Will check it out.


Your reading of just 8Hg (inches of mercury) is low.
8 Hg is per Shop. I just had a hand vac without going to the trouble to set up a constant vac at 8 Hg to test each system component - hence the test of just the check value at this point.


Hard to think a TSB this late just decided to show up now but could have.



My thoughts too, that's why I asked.

Thanks for all your input.

=========================

Now to pull dash whichis a #$%^@ on this vehicle.

Response From Tom Greenleaf

OK - if vacuum is regulated to only 8Hg than so be it. That item could leak too.


Why are you pulling dash? Yes it's a total pest on most everything but be sure you need to,


T

Response From dw8 Top Rated Answer

FWIW:

Used my hand vacuum pump and tested vacuum lines.
Everything appears to be OK vacuum wise.
There is a water value that controls flow to the heater.
Interestingly, per shop - if I am reading manual correctly (don't know how to upload pics for a second opinion) - the water valuve is only shut off in "A/C recirculation" mode.
Also interestingly, is when climbing a hill in A/C recirculation mode, no air is diverted from other vents to defrost.

Still have noise and when / if find the solution will post.

Response From Tom Greenleaf

There's your clue! Look at that water valve and see if it's also actuated by vacuum. Truth is that is either to delay heater blower or adjust flow volume for heater temp setting but the choice of recirc vs fresh air is yet another diverter door quite possibly run by vacuum also - just don't know every vehicle's way without a hunt.


So if that put the mode door (panel, floor, defrost or mixes thereof) all set then the leak is to do with that.
This just smacks of a leak of vacuum not yet broken entirely plus the noise could explain both. Reading if true of 8Hg could have meant 18 Hg or be because of the leak and not enough while leaking. BTW - vacuum available while running will vary from zero to spikes up to maybe 22 or more when engine is braking vehicle as in down hill. Doesn't matter the storage ball idea covers all that normally.


This is somewhat common especially with plastic (but rubber too) failures anywhere the integrity of vacuum is compromised. Usually near something that moves or in the way of something that you might touch to do something else plus if touching something hot they can melt a total hole now partial.


Again those plastic lines look a lot like wire but end up with rubber ends or elbows as needed.


More: If this is at the control head inside, diaphragms inside or hoses involved it will be a pest to be sure, worse if control head itself is plain worn IMO. Had those apart and wonder why some last for crap.


You may find multiple vacuum connectors here and there of rubber and a way to fasten that's either loose or broken too.


I really hope you can create the noise and find it by listening. Try tricks like using a long snouted funnel, plain stretch of hose might do, Once found the fix should be clearer what it will take.


Oh - for pics try using a hosting site like photobucket or tinypics is another. Link to the pic or try if it will show directly via copy/paste or whatever your device's way is,


T

Response From Double J

Get a copy of TSB 24-12-94

Sounds like the condition you describe.


Here is an excerpt.....

Symptom/ Condition:

Under certain conditions, the internal flow of R134a refrigerant may set up a resonance in some evaporator cores.
This resonance can emit from the dash area as a high -pitched whistle noise. The whistle noise usually lasts 3-5 seconds and starts shortly after the A/C Compressor clutch engages. The duration and intensity of the whistle noise may vary as well as be highly intermittent. The whistle noise is most likely to be experienced at ambient temperatures above 85 degrees F and engine speeds around 2000 rpm.

This bulletin involves installing a different type of expansion valve.

Part # 4677334 expansion Valve
Part # 4677045 Gasket -Ex Valve to Evaporator
Part # 3846834 Gasket -Ex Valve to Refrigerant line