Rb20Det R32 Gtst Rough Idle

[ZRBE]

Wasn't keen on starting a new thread..

R32 gtst - RB20DET

When I start the car whether its first thing in the morning or after the car is hot; The car sits at 1500-1700 RPM and doesn't drop... Ever, also has a spluttering/popping noise on idle & deceleration..

It's slowly getting higher & higher for example about 2 months ago when I started driving it after about a year off the road it was between 1200-1400..

I've gone through 3 different coilpack sets, same problem.

Cleaned AAC, same problem.

Found 2 small vacuum leaks, still didn't fix the problem..

Next will be injectors I guess.... Or any other opinions?

I'm actually taking the car to Gavin Woods at southport to plug the ECU in and see if any fault codes pop up.. So might tell me the problems cause.

Edited January 20, 2014 by ZRBE

[GTSBoy]

Remove the air feed hose from the crossover pipe that runs to the idle speed control gear and block both openings. See what happens then. If it continues to run fast, then air is getting in somewhere else.

[ZRBE]

Remove the air feed hose from the crossover pipe that runs to the idle speed control gear and block both openings. See what happens then. If it continues to run fast, then air is getting in somewhere else.

Will do, thanks man! Damn you have some knowledge... Aha

EDIT: So my car should stall after blocking both openings?

Edited January 20, 2014 by ZRBE

[GTSBoy]

I wouldn't do it running unless you can do it quickly, because you will be opening big holes into the air flow. But if you were to do it with the engine off and could restart it (maybe needing some throttle opening) and it then stalls or chugs along at 300 rpm sounding like a kero engine....then the air flow path to your fast idle would appear to be through the idle control valves. If it continues to run fast, then not so much.

[ZRBE]

I wouldn't do it running unless you can do it quickly, because you will be opening big holes into the air flow. But if you were to do it with the engine off and could restart it (maybe needing some throttle opening) and it then stalls or chugs along at 300 rpm sounding like a kero engine....then the air flow path to your fast idle would appear to be through the idle control valves. If it continues to run fast, then not so much.

Okay, so to get this straight if I do this and engine runs at 300Rpm or just stalls; There is no vacuum leak?

But if it continues to run higher rpm, it's safe to adjust the 'idle control valve'?

Sorry lol..

[GTSBoy]

That's alright. If it runs slow or stalls then the problem (whatever it is) is in the idle control gear (either the fast idle/cold start thingo or in the ECU controlled AAC). If it continues to run fast then your air flow path is somewhere else - some other broken vacuum hose or gasket or whatever.