Erratic Idle On Rb20

[Renee]

Hey guys. I have an R32 with an RB20det engine. When the car has just about reached its normal temp after driving for a few minutes the idle plays up. For example when i pull up at lights i notice it being erratic. Anyone know what the problem could be? Thnaks peeps.

[Wheezy]

Easy fix.

There is a valve known as the IAC hidden under the throttle body. Clean the contacts on the plug and on the valve and it should return to normal.

Also give the valve a blow out if ya can.

[paulr33]

try an ecu reset when the car is at operating temp

[blockasR32]

airflow meter might be f**ked thats wat mine was doing and wouldnt go over 2500rpm

[BettyBlue]

mine has the same issue, thought it might be the afm, since when it was on cold start he was fine, no such luck though. lately in hot weather he's been sitting fast at 1200 for no good reason, not a boost leak either. *shrugs*

he still does it occasionally, but a little heel/toe here and there stops the rare conking out

might try the IAC myself, thanks Wheezy

[Habler]

My mates does the same thing... Just always assumed it was the TPS. Im guessing the IAC and TPS could be the same thing

[blockasR32]

could also try to make sure that the connectors in the plug for the afm are contacting good

[Renee]

Thanks guys ill give these ideas a go when i get a chance. Its just weird that it only does it before it reaches its regular tempreature. Once it has warmed up it doesn't do it anymore. Ill let ya know if these suggestions work. Thanks

[paulr33]

ive got a mate with the same problem - identical to what you said

funnily enough we put an rb20 ap eng powerfc in his car on thursday night and it fixed his idle

he also had starting problems, it would never start with the stock ecu, he had to almost flood it (carby style) to make it start

it started first crank with the powerfc

let us know if you find somthing

[daisu]

My mates does the same thing... Just always assumed it was the TPS. Im guessing the IAC and TPS could be the same thing

TPS = Throttle Position Sensor

IAC = Idle Air Controller (also called AAC valve, Auxillary Air Control valve)

I would say it would be the IAC, you need to remove it from the inlet manifold, pull it apart and give it a good clean. It will be full of old soot and oily gunk.

If it was idling funny all the time I would suggest checking the TPS.

Edited January 25, 2008 by daisu

[Renee]

Hey guys i cleaned the IAC and its all sweet thanks heaps!

ive got a mate with the same problem - identical to what you said

funnily enough we put an rb20 ap eng powerfc in his car on thursday night and it fixed his idle

he also had starting problems, it would never start with the stock ecu, he had to almost flood it (carby style) to make it start

it started first crank with the powerfc

let us know if you find somthing