New IAC Valve - Toyota Nation Forum : Toyota Car and Truck Forums

Bugdoc · 09-09-2004, 07:22 PM

Hi all, well had some stalling problems and had dealer install a new IAC valve in my 97 Camry 4cyl. New IAC valve fixed problem no more stalling. A note on paper work said they also cleaned throttle body.
I have noticed one difference since new IAC. The early morning cold starts- the RPMs go up to about 1800 but instantly drop to 1200 rpms staying there instead of my usual 1800 or 1900 cold RPMs . then eventually going down to the normal 600. I did not think replacing the IAC valve would cause any difference in the cold start rpms. I assumed that was set by the ECU. Engine is running well but I am wondering why the cold rpms would change and be lower ? My area ambiant temperature is about 80 degrees right now, winter is usually in 30s. Could that be a factor, I always remember it going right up to 1800rpm if left for 24hrs regardless of outside temp. Any inputs appreciated

Vince

Quickbeam · 09-10-2004, 08:31 PM

I think you're good. With a new IAC, a cleaner TB, and an ECU reset, it's not uncommon for the computer to learn the new conditions and adjust accordingly. Everything is running good though, right? If so, I really do think everything is okay.

Bugdoc · 09-10-2004, 08:54 PM

Yes engine seems to be fine otherwise. You mentioned ECU reset. I was wondering about that myself., I was wondering how to reset the ECU myself, thinking maybe New IAC install may have corrupted the ECU memory, Do you think the dealer should have or would have reset the ECU after the work done??

Vince

Quickbeam · 09-10-2004, 09:40 PM

They definitely should have reset the computer. If not, whoever worked on your ride is a real dickslap. Easiest way to reset is to disconnect the negative batter cable for about a minute. Start the car up and let it run for a few minutes w/o any accessories running and w/o touching the throttle.

Bugdoc · 09-13-2004, 05:34 PM

Well just for peace of mind I reset the ECU myself via battery cable. it still cold idles at 1400 rpms I guess I will see what happens when it gets real cold out 20 or 30,40 degrees maybe the cold idle will be up to the the usual standard 1800 rpm at that temperature. Thanks for your inputs really appreciate it
V