2002 Protégé 5. P0507 Idle Control System RPM High. When it's cool out and I start the car the idle shoots up to 2600 RPM then drops to around 2200 RPM after a couple seconds. If I touch the gas pedal at all it shoots back up to 2600 RPM until the engine warms up, then it goes back down slowly. I also noticed that once the engine is warm and I come to a stop it takes two or three seconds for the idle to come back down.When I push the clutch in when shifting the RPM’s go up by a couple hundred. I did not initially get acheck engine light.After a couple months of this the light finally came on. I did clean out the Idle Air Control Valve a month and a half ago and it made no difference. It's a manual by the way. I hope someone has some Ideas to share on this. Thanks.

 

Did you ever solve this problem? I am having almost the same exact problem and replacing my IAC did nothing.

 

I found this on google referring to a Chevrolet:
- Dirty throttle body
- Electric throttle control actuator mis-adjusted or damaged
- Faulty Electric throttle control actuator
- Intake air leak
- Poor electrical connection to the Intake Air Control (IAC) valve

I don't no if the 02 protege has an electric throttle control. Clean the throttle body both outside and inside. I hope it helps.

 

I have already replaced the IAC with no improvement and will be going through that list to see if any of it will help.

 

Turns out that my accelerator cable was not allowing my throttle to close all of the way. Its fixed now and running well.