From cold the engine starts and ticks over fine. As the accelerator is pressed there is a slight delay before the rev's increase then after that the occasional misfire. As it warms up the misfires get worse till it wont tick over and sounds like its running on 3 cylinders. Eventually it wont tick over and stalls.

Checks so far:

- ECU reset, No code showing.
- All coils tested with strobe and seem to be working.
- Unpluged MAF on tick over and engine dies straight away, so am guessing thats working.

I'm lost now Does anyone have any suggestions?

 

perhaps a failing plug or lead

 

Leads are new performance ones so I'm ruling that out and all the plugs seem to be fine.

 

i had the same problem with my tommy kaira and all it was was the leads. Changed them and away she went

 

has it only happened since you replaced the leads?

 

Plug leads on a 93?

Coil packs maybe or plugs need gapping to .5/.6

 

Its definitely heat related. About 30 seconds after starting the car from cold it starts to misfire. So am starting to think its something worse than just leads. It died whilst on full boost and it had slightly to much oil in it, could it be a mechanical problem?

 

Sounds like plugs, or coil packs heating up and breaking down.

 

All coils seem to be giving off good sparks, I pulled each off inturn whilst running the engine. There are no cracks in any of them and each tested at 50ohms.

Shes getting towed to the garage now... this is going to get expensive

 

to much oil can cause problems, it can also affect your boost solenoid however I dont think this would cause your misfire. It may be a case of removing all induction pipework and the intercooler and checking for oil in there. If there is then give it a good clean out with something suitable and drain some oil so that you are with the min and max range.

 

also meant to say check all induction pipework make sure something isnt split or cracked

 

Is that the only problem having too much oil would cause? I'm guessing it would increase the oil pressure slightly. Maybe increased pressure behind the cylinders leading to mechanical failure. I'm hopeing its not this, but its not making any nasty noises so fingers crossed its not that.

 

How could too much oil effect the boost solenoid?

 

Timing belt slipped one tooth. All fixed now, bloody lucky it didn't slip more than that!!

 

bloody lucky there fella my 93 wrx wagon is sat on me driveway waiting to have a service and cam change but cant afford it at the mo so thought it was best not to drive it until the work is done!!