The other day was the first time i really put my WRX through a full day of stop and go driving in summer heat. I was sitting in a drive thru and noticed that it was idling at 1500 rpm and the temp was just a hair below redline. I quickly turned off the AC and it jumped to 2000 rpm. I drove it for a couple miles and cooled off and rpm's were normal at idle. All it needed was for the reservoir to be filled with coolant and it's fine now. My question is, is it normal for the rpm's to raise to compensate for increased engine heat, or is something out of whack? I've never known a vehicle to do this in an overheating situation.
Ive never heard of anything like that. I'm guessing it was because of overheat issue. Try to monitor it and see if it does it again. Wait till it gets to full operating temp and turn it on and off and see if you can get it to duplicate.
ive had that happen to me a few times on my 03 just mines not over heating, cant figure it out either. i think my throttle body gets gummed up or somethin becuase if i open hood and press it back everything is normal. is there a way to stop that?
The fans work properly and I actually clean throttlebody and IAC every other oil change. I tried to duplicate it today and it didn't do it. I'm guessing it all had to do with a heat issue which has been resolved. I do recall that the Ford Super Duty trucks will increase RPM @ Idle to compensate for engine heat but they on the other hand have a belt driven fan...