HI guys thanks for looking first of all great forum ;-) i will start with the car it's a 97 sti v3 has a full decat pipe and vta dump valve panel filter other than those i think its standard!

the Problem!!

When she warms up basicly comes off of choke she almost stalls jumps up to 1100 rpm and drops down again and again and again also i feel she is just holding back a little i have done the ecu check light but it says everything OK

Also i popped into my local mot garage and they tested the co and the co level is around 6.00% on tick over and around 2.5% on fast idle

they think it might be the maf sensor but were unsure!! is there a way i can test the maf or does anyone have any other ideas!!


thanks in advance Phil

 

If you disconnect the maf while on idle, if the car stalls, its fine, if it keeps running, its no good! This test doesnt always rule out the maf as I was having similar symptoms in MY94 WRX and I did the MAF test and it passed but my prob was still there. I have now cleaned my maf and WOW, what a difference. No more idle issues, no more spluttering or hesitation. A can of CRC electronics cleaner did the trick. Hope this helps. Good luck.

What I also should add is Id done coil packs, plugs, fuel filter, cleaned the pcv, cleaned everything. Nothing fixed it until I cleaned the MAF!

 

O2/Lambda sensor could be an issue, you should really get your car on a diagnostics machine, that will point out the problem

Tony

 

I had a similar problem which lead to it being a coolant sensor issue, i would check this out and ensure there is no air lock in there.

As said earlier if the MAF is disconnected the car should stall. If it doesn't try using a friends MAF if possible and testing it that way.

 

can you clean the maf with water dispersant/penitrating oil or does it have to be brake cleaner?

 

cheers guys i will try disconnecting it tomorrow

does anyone know a good scooby specialist in the colchester / chemlsford area

thanks Phil

 

The safest thing to use is electronic parts cleaner as it doesnt leave any film or residue on the highly sensitive internals of the maf. Ive heard brake and carb cleaner are a bit too harsh. I used electronic cleaner on mine and it cleaned up well and car is running better than ever.