Cleaning the Idle Air Control Valve and Throttle made things *worse*?


2000 Mitsubishi Eclipse, 2.4L, 4 Cylinder

I had some rough acceleration at times, so I got some of that spray cleaner and cleaned the Idle Air Control Valve and Throttle and now it drives a little better but the the idle is terrible. It’s a real battle trying not stall at stop lights and at start up.

On cold start I will hold the gas pedal to get revs a little high, but it revs back and forth 1000-3000 rpm, even thought I am holding the pedal steady. Once it gets warm it will no longer rev high like that, but it will stall on its own. I did spray the idle air control valve (unplugged) with that cleaner, could I maybe have fried the valve by spraying it? Any advice would be appreciated.

edit: I just realized looking at the spray bottle that I used Carburator Cleaner, CRC Brand instead of Throttle Body / AIr Intake Cleaner. Could that have caused the problem?


Type of the cleaning product is unlikely to cause much trouble, IMHO.

For Nissan, after doing throttle body cleaning you are supposed to run “idle control self-learn procedure”.

I can imagine for Mitsu you would still need to do something similar, but the actual procedure might be different… Google for it!


The throttle position sensor may be the culprit.




Carburetor cleaner can damage the idle air control motor. The safe way to clean that type of throttle body is to remove it from the engine, remove the IAC motor, clean the throttle body and IAC port and wipe the tip of the IAC motor. Do motor spray into the IAC motor.

About 15 years ago a co-worker sprayed a cleaning product into the IAC port on a Mitsubishi 3000 GT with the engine running and dissolved the tip of the IAC motor. The IAC motor in your throttle body appears to also have a plastic tip.


Inconsistent idling can be caused by numerous things, but if you think it is a throttle valve position problem, the best way to address that as mentioned above is usually to remove the entire throttle body from the engine and clean/inspect it on the work bench. The egr and pcv system can pollute the back side of the throttle valve, and you can’t easily reach that area by spraying cleaner into the intake side of the throttle body. A throttle valve position problem wouldn’t usually cause rough acceleration tho, so I expect you’ve got some other things going on there too. Make sure you read out all the diagnostic codes from computer memory first.