Hey guys, since it got warm out my car has been doing some funny idle things. I'll try and list what all I can remember.

2002 WRX
2.5STi block forged pistons
12mm oil pump
autronic sm4
stock 2L heads
stock turbo
catless turboback exhaust
ATI super damper

It was dyno tuned in the winter after running a summer and half the winter on a slightly less aggressive and much richer road tune. All summer I had a few semi-warm start issues (shut off for around an hour or two and cooled slightly) when i'd start it the revs would bounce a bit. This was corrected mostly by my tuner but would occur much less severely sometimes.

After the tune it has been running perfect until after the first rain/thunderstorm since it warmed up. The morning after the rain I started it and it revved up all the way to 2000-2500rpm and I could not make it go down. I decided to drive and after I drove a bit and it warmed up it was idling fine. It did this a couple more times and seemed to stop. A couple other times I started it and it cold and it would not kick up to warm up idle - it would stay around 8-900.

Now a week and a half or so later it will start good, kick up to warm up idle and as soon as i drive it the idle will not go under 1500 rpm. The usual warm up idle setting. Sometimes I can get it to bump down slightly to about 11-1200 by revving it up a bit and letting it drop.

I cleaned the IACV not too long before the swap so I'm sure it should be good - I replaced the gasket in there too. Anyone have any suggestions? I know to correct a really high idle once my tuner had me unplug a sensor near the intake and then do something with the throttle and plug it back in. It only happened once so I can't remember the procedure.

I will take it to him once I get some time if I can't figure it out but if someone here can help that would be awesome.

Cheers.

Could be your thottle cable, buy a new one and install it. Cables do go bad after time. Also take your intercooler off and check in the thottle body for dirt n clean that too. Good luck.

re-check iacv
also pcv

im assuming your tuner was checking your MAF sensor

The Autronic SM4 does not use the MAF sensor.

Sounds to me like the Autronic is not going into idle mode. I suggest you re-calibrate the Autronic TPS to ensure that's not the issue. (which is what the tuner did) Switch car off, disconnect throttle position sensor cable, switch car to on and wait 10 seconds, still with the car on re-connect the sensor cable and then take the throttle to 100% and hold it their for 10 seconds. The Autronic should have picked up new TPS calibration settings.

The Autronic uses MAP so check that it's hose is connected.