HELP! WRX trying to stall at idle and stutter
 

hi guys http://images.ibsrv.net/ibsrv/res/sr...lies/thumb.gif

thought would put this up to see if anyone has any bright ideas

had a issue whith this 93 import wrx since i got it few months ago. it seems to run fine from cold but generally at warm temp normally after 15min driving i keep getting what feels like a fuel cut off

it does it too even at a steady speed on at a flat road about 3k as well as under boost.

since it is cold weather seems to be getting worse, but may be a co-incidence

if it has this feeling of loss of power it drives normally for a bit. when pulling upto lights/roundabouts as soon as the clutch depressed and the revs drop it idle drops off to stall

i have read the codes and got maf and iacv. took iacv off cleaned it with cleaner and replaced. iacv works fine free as a bird and works fine from cold and idle

i bought a second hand maf and replaced, cleaned that before fitting but looks in good shape. reset codes and drove, problem is still there.

codes brought up maf and tps when checked again, so inspected tps looks good checked resistance while opening inlet and smooth readings.

cleaned maf again, checked spark plugs and ignition leads, fine. still have the issue.

fitted a gauge to fuel pressure line and fuel is just over 2bar to 2.5 when reved and holds pressure after engine off so think pump is ok but i have to get gauge into the car so can see if it drops with the stutter whilst driving

read about disconecting maf sensor when engine warm and runing, it tries to stall but recovers repeatedly without stall and keeps going. i heard this indicated maf was fubar

however i have also read this is bs and proves nothing

does this mean its the maf? i am going to buy another, but brand new this time.

if anyone has seen similar expierence would appreciate any insight to see if im going the right way.

thanks for reading http://images.ibsrv.net/ibsrv/res/sr...milies/lol.gif

What mods have been done to the car, if any?

not much to the engine, a blitz cone air filter, and the ecu was chipped at one time. would these effect it?

Do you know anyone locally who you can borrow a known healthy MAF from to check it before you spend any more money?

It may be the wiring to the MAF. We had one a couple of months ago that was doing very similar things, changed the MAF and it made little difference. We then traced the harness and found a wire had been up against the bulkhead and had split. Replaced the wire right up to the MAF and that sorted it.

thanks for the input, i have since got a brand new maf but although it was supposed to be a exact replacement it would not run with it over fueeling and cutting out.

i am however convinced now that the maf is fine its down to the loss of signal. i have traced the wires and was a split in a wire so i re crimped it but has not made a diffrence as it still faults

is there a way of checking if the wire from the maf is sound all the way to the ecu?

if so what pin in the ecu would be the input from maf? was thinking i could check resistance between them incase the wire has broken down somewhere?

apreciate any advice on this, thanks again for your reply

Take your car to a speciallist, they could find the problem in 10 minutes, or it could take them an entire day, you on the other hand could replace every sensor and still not fix the problem, so its best to bite the bullet and get it sorted by someone who knows these cars.
If not then I would suggest putting everything back to standard and see if that cures the problem.

Tony:)