I am trying to figure out what is going on with my truck. When I park my truck it has begun to idle up to 1500 - 2000 rpm's. Normally it idles around 500. It sounds like the engine is gona race off. What is causing this.

I had Autozone use their scanner, but the technician told me that no code was showing because my check engine light was not illuminated.

My accelerator is not sticking, and when I engage the transmission in drive or reverse it idles like you would expect it to. But it sure is a hard jerk on the transmission when going from park to drive or reverse. Sometimes it idles normally after shutting the engine off. However sometimes when I re-start the truck it idles right back to the 1500-2000 rpm range.

Any advice appreciated.

John

 

tell us make and model u got.

 

Mine will idle up around 1500 to 1600 when it's cold. Try cleaning the MAF sensor and the throttle body and the linkage real good.

 

Try disconnecting the MAF while its running and see what it does. If it goes to normal idle then theres your problem. Same goes with the Idle air control sensor. What the computer will do is realize that it isnt getting a signal from the sensor and should idle like normal instead of getting the wrong signal that causes the truck to idle to high.

 

Trouble_Maker
Junior Member

Join Date: Jan 2010
Posts: 8



tell us make and model u got.


That didn't work, I agree with this post, its nice to know the application.

 

possibly the idcle control mondule or w.e its needs to b cleaned... my truck im 95% its the problem my truck surges like it revs up a hair then cuts out then revs up does it now and then but tap the gas and shes fine

 

It's a 2001 F-150.

The ford dealership replaced the idle air control about a year ago. Can you tell me what the MAF is and where it is located? Thanks to everyone else for the advice.

On a side note. I recently had the dealership service my truck, being that it has about 154,000 miles on it. The day before they serviced it, the check engine light came on. They initially could not read a code. Later they said my GEM unit was full of water. They wanted $740.00 to repair this. I can't afford it at this time so I had them to reseal the windshield where the technician told me water was seeping in from and going down my a-post. About a week later the check engine light went off and no problems. Until the high idle in park situation a few days ago.

Also be advised that where I live we recently had 6-8 inches of snow and slush. I wonder if wtaer did not find its way back into the GEM unit and cause this problem. The snow has since melted and roads are normal again and I haven't experienced the high idle problem anymore.

Do you all think the GEM module could be the culprit?

 

What is MAF? I am having similar problem. Mine will idle high, and sometimes will idle properly.

 

https://www.google.com/search?source...4dUDCAk&uact=5

 

MAF doesn't make sense. AIC, or a vacuum leak would be more in line with your description. MAF with throw a lean or rich code, (P0171,172, 174, 175) normally. Bucking or misfiring at run up would be prevalent at times. The OP isn't saying that. I wouldn't put any money on it being the MAF.

OP, if you had a code a week ago and not now, it is still stored in the computer unless you have killed the battery or replaced it. Otherwise it is still there. I'd still check for the codes. A good reader will show if you have any pending codes also, that still haven't set off the check engine light. AZ and O"Ry's use cheap scanners, at least locally. Find a good one and try it. It should show you where to start.

On the GEM for runability, no. GEM controls electronic functions within the cabin for most instances. It does control SOTF transfer cases, windows, locks, heater, radio, etc. Everything electronic inside the cabin runs thru the GEM. Another name for the GEM is Body Control Module. That should help you understand it's functions.