[Mk2] [Turbo] Revs dropping to 300 rpm at idle

[Peter Gidden]

at idle the revs drop to around 300 rpm and car stalls unless u give it some gas..

Had a Rev1 Turbo in the workshop doing exact same thing.

Turned out to be a leaking HKS dump valve.

[joemacmr2]

Was fault intermittent?
I have the oem recirculating valve. How would I test if it's leaking. My mechanic thinks its a fault within ecu which I'm having a hard time believing. I've changed clutch decat and put new intercooler in over last 2 weeks and this problem has just raised its head so has to be linked.

As idle was low I started moving the tps about and idle didn't change but when I pulled the idle control valve connector out the revs became very healthy. Is there a 'how to' to calibrate tps floating about?

[Peter Gidden]

Was fault intermittent?
I have the oem recirculating valve. How would I test if it's leaking.

Block it off. However, OEM recircs. are high quality and rearely give problems.

My mechanic thinks its a fault within ecu.

I very much doubt it.

As idle was low I started moving the tps about

Why? Bad move. Setup procedure is in BGB.

[joemacmr2]

Cheers peter. Can't get into bgb. Have a procedure here for mk1. Take it it's the same?

Is it normal for idle to rise up to normal after pulling plug to icv?

[Peter Gidden]

Is it normal for idle to rise up to normal after pulling plug to icv?

Yes

[joemacmr2]

So my icv works then?

Probably my tps. Bought a set of feeler gauges so il set it up tonight and see how we go