i have an 02 wrx that keeps misfiring. it was doing great the first couple of months i bought it then the CEL turned on. it would always be cylinder 3 misfire (P0303). i was using iridium plugs but then i went back to stock specs. this past weekend, i changed my oil and tranny fluid and the CEL turned off. to my surprise, when i started the car this morning it turned on again. im almost ready to give up on this car. can anybody please help me out?where do i start? any pointers you guys can give me?

 

Do you have any mods on the car? Exhaust, turbo timer, any wiring? Also check your coil packs, and injectors. Usually related to either wiring or any of the stuff mentioned. Good Luck.

 

the car is bone stock

 

yea dude, i would deffinatly think about replacing the coil packs. does it shake bad? i would make sure the code is still the same, before givin up i would drive it to the dealership thats always a last resort, it may cost but they'll find out for sure, might as well ur gonna lose out givin up the car anyways. funny tho how the light went off after a fluid change. but go for coils and plugs first, the car's wired to thro CEL's for anything.

 

Yeah never give up...since the car is bone stock....has to be the one of the following. Spark Plugs, Wires, Coil Packs, or the actual injectors. Check those, it has to be one of them.

 

i just got off work like 10 min ago. i turned the car on to warm up and went to go smoke. by the time i was done smoking, the engine is already warm enough and the CEL is gone. this thing is really wierd.

 

Don't buy a new coil pack, just move it from 3 to another cylinder and see if you come up with the same misfire at the new location. That will tell you if it's the coil pack or not.