 Don't hear a thing. No head gasket. I don't think there's a head gasket issue. It's quiet on two and four. Coils, packs, spark plugs, injectors. I give up. It's progressively got worse and worse. It used to be it would start once you drove, and then when it warmed up, it would get better. Now it is dead. Both cylinders, two and four, dead as a doornail. How many miles are on this now?