2005 Altima turns on after driving a couple of hours it does not, what could be wrong?

Question

I have a code ps 302 after driving for about 2hours it does not want to turn on, it only cranks but does not turn like if there is no fuel coming thru and after an hour or two then it does turn on driveable. Can you help. I already changed coils and spark plugs

Answer 1

Start by checking for fuel pressure. Disconnect the fuel hose and make sure there is fuel pressure when you crank the engine. If there is fuel pressure, the next step is to perform a compression test. The P0302 code and hard start, are signed of a blown head gasket, which is very common on the 4 cyl. Altima