I have had a misfire for a while now. Its on 1 and 2. I've replaced - Egr valve, ignition module, ignition coils, spark plugs, spark plug wires, catalytic converter, all 4 O2 sensors, upper intake gasket, upper intake itself, all 6 fuel injectors and the pigtails for them, fuel pressure regulator, and the crankshaft position sensor. I'm so at a loss I'm losing the will to work on it.