Idle problem after repair

Not using my car for awhile, I changed the thermostat and replaced the battery. After that the idle fluctuates abnormally. Thinking it was trapped air I poured 50/50 coolant/water into the

upper radiator hose.

Although the radiator fan turns on the idle problem stay the same.

I looked everywhere for a bleeder screw but found none. Now, I’m starting to think I either damaged the computer or it needs to relearn it’s memory, because before I changed the battery I

recharged with a manual charger, therefore overheating the battery.

Is it possible I damaged the computer with this year model

or is it just a memory problem. I don’t think it’s the idle control

valve because it ran perfect before. Is there anyway to relearn the computer without taking to the shop? Any answers would be very much appreciated! Car is 2003, 2.4 liter.

Sincerely, Probie

Explain the part where you said “Not using my car for awhile” - be detailed about how long and where and how the car sat.

The abnormal idle has nothing to do with the cooling system. Problems there will show up on your temp gauge or heat functions or something.

It might be that the computer has some relearning to do and it will most likely do it all by itself. Just go drive the car.

But you could have another problem. Take a good look around under the hood for a broken or disconnected vacuum line. There should be a little schematic diagram of the vacuum system under the hood to help you account for the components and connections. Vacuum leaks can be hard to find, esp. if they are small. You can use an unlit propane torch to search or a piece of flexible tubing to listen for hiss.

Don’t discount the IAC only b/c it is the kind of thing that can just get sticky and letting a car sit for a while is a good way for things to get sticky. You could likely pull the thing off, clean it, and reinstall it in the space of about 30 minutes and at a cost of about $.50 of throttle body cleaner (and maybe a new gasket).

Thanks for the reply. The car’s been sitting about a half a year. Found or heard no vacuum leaks.
When I changed thermostat I was careful not to touch any vacuum leaks. Plus, there is no vacuum hoses near
the housing.

Ran the car on the freeway for about 20 min. but still has idle problem. Will try to clean IAC as you suggest but if it’s true that they can stick after awhile, then won’t all modern cars have that problem if not
driven for awhile? Either way I appreciate the helpful information!