I have a 2002 maxima with p0300 code I changed the spark plugs and ohm the coils they vary frome 1.5 to 1.8 I put a new fuel diaphram and pump and filter in pretty sure this is when the hard starting started but the code waz there before I did that so now idk if the spark plug change fixed the p0300 code but now maybe something happened with the fuel now making the same code come any suggestions cuz idk know anymore now
have you checked for intake leaks? check to see if the exhaust (the catalytic converter) is not clogged, check fuel pressure, it should be 51 psi and idle.
if you still have the same problem, disconnect 1 ignition coil as a time and see if the car rpm drops or starts shaking, if there is not shaking or rpm drop the coil is bad.
if none of those help check compression
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