Ok i've been fighting this problem forever now and now i'm hoping someone has some ideas of what to look for. I've got a k20z1 turboed in a 05 civic with a plug and play aem ems. the car ran great for months until it overboosted and it started missing at 3000 rpms which got worse and worse until it didn't run for shit. I found a blown head gasket which i fixed and put everything back together. after i put it back together it still ran like shit misses and backfires runs super lean and wont rev up for shit. I've put a new fuel pump in and had my injectors checked. All my coils are firing i've tore apart the engine and rechecked timing checked my sensor that i could and still nothing. I don't know where to go from here. I've got 42lbs of fuel pressure on my regulator and the car fouls plugs out super quick. I don't get how it can run super lean and miss its ass off with fuel pressure and fuel fouling plugs. Does anyone have any ideas i'm lost from things to check and i just don't know where to go from here. I'm about ready to tear the whole thing out rebuild it again and start a new.