jaytc2003

iTrader: (1)

Been out tonight in the car to drop the gf off at a works do,its an my93 wrx, and on the way home the car had a slight misfire in 4th and 5th, didnt think anything of it as the knock monitor on the commander didnt show anything to worry about.
Got home, let the car cool down, turned off etc.
Started it up a few hours later and the car was racing from about 750rpm upto 900rpm

If I used the accelerator it would only rev to about 2500 but was stuttering getting up there, again no real knock activity on the commander (think it was either 8 or 12 cant remember)
Whilst prodding the accelerator the voltage across the maf was increasing so I dont think that it is that or could it be?
It was dark so couldnt see anything under the bonnet so didnt disconnect the maf to see if it stalled.
Does it seem like a maf problem or possibly the coil packs?

LegacySTi

iTrader: (13)

Hunting you say so i'd look at MAF.

jaytc2003

iTrader: (1)

what I though, but the voltages looked okay on the commander, increasing with the revs.
Will disc connect it tomorrow and see what that does.

jaytc2003

iTrader: (1)

started it up this morning and unplugged the maf and the car imeddiately stalled.
When I reconnected the maf (engine/ignition off) and started it again, the airflow voltage on the commander was not static, is was hunting around about the 1500 - 1600 mark instead of the usual 1250 - 1300
Do you think this is the maf even though it stalled the car when disconnected?

Jolly Green Monster

iTrader: (4)

Maf on the early cars don't normally fail.. I would look at the plugs and coil packs.. the misfire in 4th and 5th point towards spark if you were on boost.

if the MAF failed the voltage would be less and it would have run more ignition and less fuel on boost in 4th and 5th when it was missing and you would have seen knock.

If you weren't on boost in 4th and 5th then it could still be spark.. or possibly fuel.. perhaps the fuel pump is tired.. need to get a fuel pressure gauge on there etc..

Also check there is not a pipe leak, intercooler (sometimes the black plastic splits under the intercooler), vac line, the air in take is leaking between turbo and maf allows it to suck air in rather than through the MAF.

Simon

jaytc2003

iTrader: (1)

cheers Simon, will check for the leak side of things, thinking about it there is only one bolt holding my intercooler on, so its a bit loose (must sort that out over christmas while im off) so it is quite possible that it is the black pipe that has seperated.

Timothy Morphy

Yes,take a close look at your intercooler pipework. I had very similar problem on my 95 uk turbo,garage changed 4 coil packs(ouch!) and made no difference. Turned out one of the three bolts that secures the plastic pipe to the back of the ic had come out! Should have been a free fix,cost me £200 in coil packs!

Tim

jaytc2003

iTrader: (1)

bugger, checked for leaks, removed my dump valve to make siure that wasnt stuck and then broke the plastinc pipe to the intercooler! ****!

On a positive note, one of the coil packs has totally disintegrated at the business end so I am putting the missfire down to this. On the downside, everywhere is now shut!
no scoob for days unless anyolne knows anyone in the manchester/cheshire area selling any coilpacks