Idle Speed Problem - Anyone Else?

[chubbzilla]

Hey all

2003 ba turbo, manual, 120,000 kms, proces west intercooler, 3" exhaust, xtreme tune 12psi.

Car is running sweet since tune, accelerates fine, only problem is when you come to a stop, depress the clutch, the engine stays revving at about 1200-1500rpm for about 3 seconds before returning to normal.

Also when sitting on a slow speed eg. in traffic (20 - 50km/h) when I come off the throttle, it continues to drive as if the throttle is stuck in that position! This only seems to happen under about 2200rpm though.

And lastly, (it only did this once) I went to take off from a set of lights, it revved up to 3500rpm all by itself, came back down, then stalled :(

I got the tune about 4 months ago and have changed nothing since, and this problem has presented itself in the last week or two. Just wondering if anything similar has happened to anyone else, or if anyone has any ideas, I'd really appreciate any thoughts

[groper]

that sounds like what happened to me when a intake manifold bolt unwound itself and fell out thus causing a vacuum leak in the manifold after the throttle body. It revs up and idles higher coz air is leaking into the engine. And it can feel like the throttle is stuck part ways open. When its idleing The PCM tries to keep the revs at proper idle rpm so it hunts around up and down a bit but it cant coz the throttle body is already closed but the air is still getting in, somtimes it evetually stalls if you let go for long enough and you may get a warning light come on the dash also.

check your intake manifold and throttle body connections are all airtight and check for loose or missing bolts etc

some of them are a pain in the arse to get to, but check them all...

Edited 18/06/08 12:01 AM by groper

[Gavin.K]

It is a vacume leak it has happened to me aswell.

GK

[groper]

I forgot to add, check all the vacuum hoses that run from the manifold aswell, one may have fallen off or might be cracked or perished...

[chubbzilla]

Thanks heaps guys, I'll check them all out :D

[chubbzilla]

Hey, good news, I found a hose that had simply popped off it's fitting. I was pretty stoked that it was such an easy fix!! Thanks guys for the advice

[groper]

no worries mate!

try and cablie tie it on or use hose clamps etc otherwise its gonna fall off again...

[XR06T]

which hose?

[chubbzilla]

It was a rocker cover breather hose, on top of the rocker cover, in the middle, towards the back (just behind the crossover pipe). I spent a minute looking all around and under the manifold before I even noticed it, didn't expect it to be in such an easy and obvious place!