Hello everybody
I have problem with my GMC Jimmy 00 and it was start when I pulled the IAC sensor and clean it. Now my car rpm high at idle and when I push break paddle or I remove my foot from gas I can feel the rpm still high but sometimes its become normal at idle and engine light turn off by it self.

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1. when I first start the truck the idle revs up and comes back down
2. I wait for the idle to come down before shifting in to drive and after I shift in to drive it revs back up and then comes back down
3. While drive at 80kph I can take my foot off the gas and the truck stays running at 80 cause of the high idle.
4. While driving if I put the truck in neutral it revs up, if I give it a quick shot of gas to get the RPM's down they go higher and stay there till i pull over and come to a complete stop.
5. When i come to a stop light or sign the truck is running at a high idle and is hard to stop but after I stop it will come back down after 2-3 seconds.

 

I had this happen once. Did you disturb the throttle cable at all? Check your cable at the throttle body. Sometimes it can stick or the cruise control can get hung up.
Otherwise, it sounds like air is getting in somewhere past the air filter. Double check that everything is properly connected and tightly sealed, especially anything you recently took apart.

 

Yes I have removed throttle cable and cruise control when I change the upper intake manifold gasket.But the problem directly come after I remove the IAC.
I hope its from throttle body cable not from IAC.

 

I check the cable at the throttle body I see that when I move throttle plate at side the cable become loose not tight can the problem cause from this?

 

Sounds like maybe the throttle plate is jammed or the return spring isn't working? If you manually move the throttle plate, and then let it go does it snap back closed?

 

Having this problem right now with my 00 jimmy as well. I however did not remove the TB or the IAC or anything of the sort, I just cleaned the TB spraying it from the top and manually (read this could be the mistake) moving the butterfly to get the bottom side. I got code P0507 the day after I cleaned it and started getting the high idle. I cleared the code with my scanner, it came right back and the idle is still high. I pulled the battery to clear, same thing. I found some postst saying try to disconnect the battery and pumpt he brakes 3 times and reconnect. I did it and the code is gone on start up and idle seems ok but I need to test drive it but that won't be till tomorrow morning but maybe give that a try. Seems to reset/relearn the ECM somehow.

 

I actually just let it warm up and took it for a spin around the parking lot loop here and it is idling just fine. I still need to drive it at speed on the freeway etc but so far so good.

 

Yes it return but the throttle cable not tight when I move the throttle plate

 

maybe I will try to make these if I didn't found the problem. Tell me if the car now still idle good