WRX STI version 1 no extensive mods,Car starts and runs for about 10 mins fine then misses and back fires through exhaust and eventually dies ,wont start for 15mins then spluters into life with a bit of a misfire and will then run OK all day,playing with the alarm/immob no difference,things that have been changed before and after I got the car ,MAF ,ECU,fuel pump, crank sensor ,cam sensor,coil packs ,no ecu fault codes ,any idea? ta Colin

 

fuel filter full of crap?

cat collapsing in exhaust?

you have changed all the obvious ones...

 

Seems ignition related due to the intermittent back firing but what else do you change ?

 

ignitor?

 

Where?

 

behind the bracket the boost control solenoid, and map sensor are bolted to.

It almost sounds like a wiring problem but then weird that it seems time / heat related.

Simon

 

Water temp sensor possibly?, as it gets hot it goes open circuit, fooling the ECU that its very very cold, hence goes very rich, and will flood a warm engine upon restart.

happenned to me, your scenario sounds similar