Prasius

iTrader: (1)

Basically as above. 2002 STI driving fine, then when idling (with or without gear/clutch engaged) revs raise and fall by 1000rpm or so. Causing me some mild panic at junctions and roundabouts, but drives fine during "normal" road conditions.

PSI3 unit shows lambda readings normal with open throttle, peaking at 1.5 at idle with closed throttle, and taking considerable time to drop down to a .99/1.0 reading when going from partially open to closed throttle while driving. A/F readings appear normal.

If I reset my ECU using the PSI3 and then restart the engine - it runs fine for a minute or so, then starts doing the rev-see-saw.

It's booked into Baldock Subaru for Friday (which is great but I've got to get to Lincoln on friday, to be in Sailsbury for Saturday evening, and then I'll have to get back to pick it up from Baldock at some point the following weekend ).

Any idea from the description above what it could possibly be. For some reason my PSI3 isn't supplying me any error codes. I've had a Lambda go in another car but I haven't experienced the up and down revving before.

Any suggestions to what it may be, and the horrific bill I'm going to be faced with to fix it, is welcomed - to put my mind at rest or otherwise.

Ian.

Midlife......

iTrader: (2)

look at the PSi3 "historic" error codes to see what error codes have been stored on the ECU.. Access by pressing the error code button twice

Could be the ICVS ? if so prepare for the nose bleed when you hear the cost of a replacement !!

Shaun

Prasius

iTrader: (1)

No error codes are showing up on the PSi3 - but mine has an alarm flashing due to an unrelated fault with the PSi3 anyhow, so that might be why it's not reading the error codes.

I've just resigned myself to it being a faulty ICVS - I figure if I expect the worst then anything less than that is a bonus. If I wasn't overwhelmed with paranoia I'd drive it back home, but I don't fancy 100miles in limp mode up the A1.