So I'm going to be as brief as I can and hopefully some wrx guru will have some advice.
I have a 03 wrx and it has a minor idle problem.
He goes it, my car idles funky, around 1200 rpm all the time, (before the check engine light came on it idled at 500, 600 rpm)
First it has little to no effect most of the time because I usually drive at more than 1200 rpm. However sometimes when I'm stuck in traffic it's a total PIA!
About a month ago the check engine light came on and this problem started. First I went to Auto Zone and had them check the code (Iím somewhat savvy when it comes to cars so I know what the IAC sensor is, the TPS sensor etc, I can change my own oil, break pads and rotors the minor stuff).
The gentlemen at AutoZone said itís the IAC sensor (Idle Air Control sensor) had them check the price and itís like 450 bucks. I was going to say Eff it and buy the sensor but the very next day it was hot outside and the car went back to Idle at 500 rpm and I unplugged the positive terminal for 60 seconds and started the car and it ran fine with no problems plus the check engine light went off. What FUNK is this, so now in my head I'm thinking weather has a minor roll on this problem which is kind of bizarre to me?
Any who, throughout the week on the hot days the car only after driving a substantial amount of miles would go back to normal and I would unplug the terminal and fantastic, its good to go. Well, until the car sits over night it goes right back to the same problem. Any ideas anyone?? When the check engine light is on and I'm getting on the car some, I can feel hesitation (this is no good because my car got spanked by an old school Acura today, the kids was impressed, I was not).
Some of my friends say clean the throttle body, others say just buy the sensor, but what gives, and sometimes the car is okay. Now I can not get my inspection sticker because of the check engine light and if you live in MA you know the "fuzz" will pull you over for anything, and I can't afford anymore insurance violations. My father said this doesnít sound like the IAC sensor, he said it sounds more like the TPS sensor. I'm trying to avoid pulling the intercooler off to clean the Throttle Body, looks like it could be a pain, and then again Iím not sure. I have no mods to the car; itís a standard and an O3. Hit me up if you can help, thanks guys/gals.
TheReplacement: thanks for the comment, I never use A/c and I tried turning the defrost off and on, no change but thank you for the advice. Iv'e only had the car for 3 months and I called the previous owner and he told me to check all the vac hoses because he had the check engine light problem in the past so on to the dealership I go..Booo 115$ per hour!! Hopefully its a lose or disconnected hose.