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Pete
Pete, Auto Service Technician
Category: Dodge
Satisfied Customers: 27157
Experience:  Over 17 years diagnosing and repairing automobiles various makes and models with some training and certifications.
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2001 dodge p/u 4x4 auto trans. k miles one owner. a couple

Customer Question

2001 dodge p/u 4x4 auto trans. 69 k miles one owner. a couple of years ago my p/u developed an erratic idle problem lt revs up 4 to 500 rpm at idle and while driving down the road. it started when I used cruise control now it does it all the time (cruise control or not) the only way i can get it to stop is to stomp on the gas get high revs and get it up to 80 to 90 mph and it quits till i turn it off and starts again the next day. a friend bought a 99 dodge p/u 135k miles with same everything and has the same exact problems. he took his dodge to a dealer 3 ties and have not been able to fix the problem. Any ideas
JA: Have you checked the fuse? What size is your engine?
Customer: What fuse? I think 5.6 eng or what ever was standered for that yr
JA: What is the model of your '01 Dodge?
Customer: 1500 stl 4x4 club cab short bed
JA: Are you hoping to fix this yourself? What have you tried so far?
Customer: fix myself and nothing
JA: Anything else you think the mechanic should know?
Customer: no, told you everthing I know except friends truck with same exact problems
Submitted: 9 months ago.
Category: Dodge
Expert:  Pete replied 9 months ago.

Hi my name is ***** ***** I will be happy to assist with this today.In some cases I may need more info to assist better.I apologize for any delay.

Since this occurred after cruise control was used one of the most common causes is the cruise control servo at fault.This is a vacuum and computer controlled servo that actually pulls on the linkage to adjust the throttle when cruise is engaged.There is an internal solenoid in the servo that applies vacuum to the servo diaphragm to pull the cable,this solenoid can start to fail or act up intermittently and cause this issue here.

Since it is intermittent and you can get it to stop at a higher speed I do not suspect this is a vacuum leak as this would cause the issue all of the time.This is located near the battery tray as shown below.

https://www.dropbox.com/s/kwz7njw82qbtau1/ser-08-17.gif?dl=0

The other common fault can be the idle air control motor.It can stick as carbon build up develops on this motor in the throttle body and causes this issue here.Usually you can remove the screws that hold it onto the throttle body and unplug it and clean it and its port in the throttle body to correct this.I would try this first before replacing the cruise control servo.

https://www.dropbox.com/s/dncwlzj4y8jr6lb/idle-08-17.gif?dl=0

If more help is needed, use the reply tab to continue our conversation. If no further assistance is needed, kindly rate my service,your 5 star rating is appreciated.You can rate at any time and we can continue to work on your question as this will not close out your question.Keep in mind in some cases it can be difficult to fully diagnose or help repair your vehicle without seeing it and I work on delivering the best possible answer from what I see to work with.

Thanks Pete