My 02 WRX wagon was misfiring in cylinder 1 and 4, and then 3. I don't have any mod on the car. It doesn't matter hot or cold, low or high RPM, it'll misfire. I change all four coil packs and all four spark plugs, but it still misfire.
I also have a boost leak problem, I tested the engine, but I couldn't find any leak or hiss in my car. It was only holding 3 pound of boost, so I finally decided to take it to my mechanic, but he couldn't find anything either and only got it up to about 9 pound. I then decided to take it to the local Subaru dealership in Costa Mesa, they couldn't find the leak either, but got it up to 10.9 pound. They also look into my misfiring problem, they'd change my MAF sensor thinking that it cause my misfiring. I took the car home Saturday, and Monday morning while driving to work the car misfire. The boost leak and the misfiring are still there. I decided to do a compression test on my car yesterday, 3 of my cylinder shown 150 psi, 1 cylinder only hold 139 psi.
I want to change the head gaskets and take care of the boost leak, but I can't do either of it myself. I need a better mechanic to take care of my car. Any one out there in the OC that have a good mechanic, please recommend him to me. PLEASE HELP!!!!!!