VX SS rough idle

[wassup353]

G'day,

My manual VX SS has recently started idling low (about 400 - 500rpm) once it has warmed up. It's fine when cold.

I have recently had a mafless tune done by Oztrack Tuning and a full exhaust upgrade (about 2 months ago)

I went to top up my transmission fluid a few weeks ago and when i got back in the car it was idling bad, don't have any idea but it almost seemed like it was the tranny fluid that caused this as it happened instantly after i started the car after topping up.

Swapped O2 sensors with my mate and that didn't fix it, have done a pcm reset and idle learn feature which didn't work either. Whether the clutch is pressed in or out doesn't make a difference to the idle.

Any ideas???

Cheers.

 

[kangavxss]

G'day,

My manual VX SS has recently started idling low (about 400 - 500rpm) once it has warmed up. It's fine when cold.

I have recently had a mafless tune done by Oztrack Tuning and a full exhaust upgrade (about 2 months ago)

I went to top up my transmission fluid a few weeks ago and when i got back in the car it was idling bad, don't have any idea but it almost seemed like it was the tranny fluid that caused this as it happened instantly after i started the car after topping up.

Swapped O2 sensors with my mate and that didn't fix it, have done a pcm reset and idle learn feature which didn't work either. Whether the clutch is pressed in or out doesn't make a difference to the idle.

Any ideas???

Cheers.

Had the same problem with mine. Got the tuner to adjust the fuel trims in the tune and it idles good now, so go back to your tuner and ask them to adjust it.

 

[wassup353]

I contacted Steve from Oztrack and he said it couldn't be the tune as the tune doesn't change in the PCM so if it was operating fine after the tune it must be something in the car. I might have a fiddle with the idle control screw on the throttle body and see if that helps.

 

[Schwuppes]

try changing coil packs or EFI module?

 

[kangavxss]

G'day,

My manual VX SS has recently started idling low (about 400 - 500rpm) once it has warmed up. It's fine when cold.

I have recently had a mafless tune done by Oztrack Tuning and a full exhaust upgrade (about 2 months ago)

I went to top up my transmission fluid a few weeks ago and when i got back in the car it was idling bad, don't have any idea but it almost seemed like it was the tranny fluid that caused this as it happened instantly after i started the car after topping up.

Swapped O2 sensors with my mate and that didn't fix it, have done a pcm reset and idle learn feature which didn't work either. Whether the clutch is pressed in or out doesn't make a difference to the idle.

Any ideas???

Cheers.

If its not the tune then you can get rough/low idle if your pcv valve/hose is blocked or buggered (i think they cost around $100 or so and the new ones are better quality
and dont crack at the joins.)

 

[wassup353]

Update: the car seems to idle fine once it is moving!? But when it gets below 10km/h just goes back to dropping down to 450ish rpm again...

 

[bgcarter1]

Update: the car seems to idle fine once it is moving!? But when it gets below 10km/h just goes back to dropping down to 450ish rpm again...

Any updates on what was causing the problem???

 

[DjYalla]

I contacted Steve from Oztrack and he said it couldn't be the tune as the tune doesn't change in the PCM so if it was operating fine after the tune it must be something in the car. I might have a fiddle with the idle control screw on the throttle body and see if that helps.

don't touch it... the long term fuel trims may be effected as well which happen over a period of time. When you say rough idle I'm guessing you mean you can't pinpoint it down to a single cylinder?

 

[richardpalinkas]

Try cleaning the iac, it may be full of carbon. Then do the idle relearn procedure