2004 Toyota Corolla Idle Problem - Toyota Corolla, Chevy Prizm (1998-2008)

Hi, the idle in my corolla is running low while in all gears(park, drive, neutral and reverse) it is running at about 500-600 on my tachometer. The car seems to shake a bit more while in idle, but i suspect this is because of the low RPM's. Im wondering if this is a problem I could fix or if I need to take it in. The car has 41K miles on it and has no other problems.

(I put in a K&N air filter for my 1.8L engine about 2 weeks ago and it has been running fine until now. I dont know if this is the problem though.)

Thanks for any help default_smile

Idle speed is set by the engine computer - so there really isn't anything you can "adjust" to bring it up. If this is something fairly recent - like after you installed a K&N filter on the car - then I would suspect some fouling of the MAF sensor or the throttle body itself.

Double check that the filter has not been over oiled (very common/easy to do) - check that the MAF sensor is clean. If there are any traces of oil on it - clean it with some throttlebody cleaner, alcohol, or non-clorinated brake cleaner. If the throttle body hasn't been cleaned yet - might be a good idea to give it a godo cleaning. There are several ways to do this - much of this information can be readily found online.

Also, it is a good idea to reset the ECM anytime you make a change to the car. This will allow the car to adapt to the new modification correctly, which I assume is what has not happened here (ECM say a difference in air volume from either the freer flowing filter or fouled MAf sensor, and adjusted engine parameters accordingly).