sti v5 type r 1999, car idles between 700 rpm and 1500 rpm, drive car hard and soft sometimes its fine at 700rpm then some times it drops to between 1300-1500 rpm can anybody help or advise me, i have fitted throttle body, new gasket and brand new air flow sensor any ideas cheers

 

Its a funny request, but turn your aircon on and see what happens, its not a fix but chances are its your MAF (did you buy new or 2nd hand and did you touch the maf when fitting? and does your car have an induction kit fitted?)
Oh and dont rag your car, if it is the maf all you will be doing is killing your engine

Tony

 

I too would have gone with MAF on that year car,Have you tried an ecu reset with the connectors under the dash to see if you have any fault codes?

 

its a brand new maf from suabru and its a genuine airbox fitted, i checked fault codes and code 24 & 31 were recordered, since fitting throttle pot i have reset ecu and there are no faults showing now and car seem to be better but revs still raise sometimes to 1200 just not sure if its fixed yet

 

Sticking Idle Control Valve ?

It may have failed, but it's worth removing it and cleaning out the orifice in the throttle body and plunger on the valve - they can get coated and gummed up in oily carbon deposits.

 

What Fiestaboy said. In addition, you say you've fitted a new throttle position sensor. Is this a new one, and have you calibrated it?

If not, either get hold of a select monitor/datalogger or, connect a digital voltmeter between the TPS signal at the ECU (B136 pin 19) and the sensor ground (B136 pin 17/18/24/31, take your pick). Then, with the engine idling, loosen off the pot mounting screws and rotate it in relation to the throttle body until you see 0.48 volts on your meter. Tighten the screws with it in that position. See what that does to your idle stability.