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I've done a search on what it could be, but all the information I am finding is for either the 1.6 or 1.8 NA's.

So, my problem started on Monday morning when I noticed my idle wasn't "right". It was idling very low, and inconsistantely ... It basically sounds like I have lumpy cams.

When I come to a stop and the car is still cold, the car will idle anywhere from 1200 to 1800rpm (it goes up and down, it would seem like a vaccum leak, but all the lines have been changed) then it will return to normal, then a few seconds later, the idle will dip below 500rpm, almost stall then come back to idle at 800rpm and run rough.

When accelerating, it feels like the car is delaying a response, so I give the accelerator pedal another push to get the revs up.

When it's warm, the idle doesn't dip as much, however after work today and a bit of playing around, it has started to dip as it were cold.

We unplugged the idle control sensor under the throttle body, and it seemed to run better without it, So we are thinking this is the culprit.

Lately the car has taken a few seconds longer to kick over, and it feels like there is a slight hesitation under 3000rpm (I.e lack of power) then suddenly gains power after that. These could be unrelated, or even my mind playing tricks on me.

Has anyone had this issue with their NB before?

TPS working OK?

nb8a, so may be a coilpack.

I don't know, is the car ment to stall or respond when the TPS sensor is plugged out? I think idle went stable when pulling the TPS out or was it the ICS mmm. I might try driving home without the ICS plugged in today to see If there is any change in idle.

Plug leads! (my favourite)

bruce wrote:Plug leads! (my favourite)

leads are almost new, can't be it.

Check the EGR valve before you spend any money. They get dirty and stick open, which will result in a vaccum leak ( internal, exhaust gas into the manifold).
There is only two bolts holding them on, so it is easy to remove and clean, there is a steel shim gasket between it and the manifold , which will fall down when you pull it off.

bretauto wrote:Check the EGR valve before you spend any money. They get dirty and stick open, which will result in a vaccum leak ( internal, exhaust gas into the manifold).
There is only two bolts holding them on, so it is easy to remove and clean, there is a steel shim gasket between it and the manifold , which will fall down when you pull it off.

the EGR has been blocked off due to the new header design having a different location for the EGR.

I will have a look tonight to see if it's clogged.

Ok i had some time to play around with it today. Turns out that the Idle control valve is doing nothing, it doesn't respond when it is being unplugged, or when being plugged in. The engine does the same thing regardless too. The TPS sensor does respond, idle automatically increases as soon as it is unplugged, and the engine no longer wants to stall, idle fluctuates less too.

I'm thinking both sensors might be faulty, it appears that the TPS is replaceable, but is the Idle control sensor? or do i need to get myself another throttle body?