Ok I'm not entirely sure what's causing my idle to go crazy. I swear my FC has mood swings. First thing that is goofy as all hell is that my car idles really low (300RPM) unless the headlights are on. If the car is at a standstill with the headlights on it will idle relatively normally. Cut the headlgights and the RPMs drop like a stone. This is strange as hell to me, seeing how if you lessen the load on the engine it drops RPMs instead of raises them breifly. Second issue is with a cold startup. With the headlights and the AC off it will do it's normal rev to 3k then drop down, however when the RPMs drop after the 3000 experience the car will bog and die. The last really goofy thing that's happened is when the AC is on it will randomly decide to jump between 300 and 1500 RPM, sometimes stalling out. Does anyone know what the cause of these issues could be? All I can think of is to check the vacum lines, as well as making sure my battery is connected well and putting out proper voltage.

 

warm car up
adjust screw at back of throttle body until idle is at 750.
rejoice.

 

Sounds like a vacuum leak is a definate possiblity. If you're suspicious of an area, spray some starter fluid around the vacuum lines when the car is running. if the idle smooths out, then you know you have a leak. this can be happening anywhere behind the AFM, so be prepared to spend a lot of time searching for it, or, better yet, if you haven't done it in the last 60,000 miles, change all of the vacuum lines for good measure.

your throttle positioning sensor may also be off, do a search for adjusting/check it if necessary.

edit: Good calla bout the idle set screw on the throttle body.. don't forget the rich/lean adjustment screw on the passanger side shock tower. it's the flat-headed screw adjustment with R on one side and L on the other.. try that for a bit more precision..

 

where is this rich/lean adjustment? my n/a has nothing over there i really would like to know because i am running SO rich

 

It's mounted to the passenger side shock tower.. I think it's pointing towards the firewall, but Im' not sure. Its a black plastic diamond with a flat-headed screw in the middle.

It won't help you at all as soon as you press the throttle, though. It's ONLY an idle mixture adjustment.