So we replaced the spark plugs, then a coil pack #2, then the fuel injector, then switched coil pack 1 and 3 (just to double check). After that I put the code reader and got a P0301 and P0339. The car gets power but won't start. It just goes "click" Got a new battery. Still miss firing and cylinders 1 and 2 are filled with gas and a little bit of oil. The mechanic said I need a new engine but. The only test he ran was he stuck a camera down in there he didn't do any other tests what else should I do?

I bought the car and it had fuse problems like pcm fuse blown and 2 other ones after replacing, the car was running okay still misfiring above 40 but not loud like it was before I replaced them and im thinking I have pcm issues because I replaced the fuel pump and the coil and spark plugs checked all the fuses even replaced the ones that were corroded and it still shows up as a p0301 and P0300 and p0303 the codes don’t want to clear up and they come back soon after clearing them anyone thinking it’s the pcm as well since it controls literally everything in the car?