2003 Nissan Altima Sedan with engine code P0300

Question

I have a 2003 Nissan Altima 2.5L, check engine code is p0300, I already changed spark plugs and one of the engine coil. and the problem continues. which is that is very hard to start the engine and takes more than one time to start. and on stops sometimes engine idle goes up and down in a not normal way. what should i do now? help, please.

Answer 1

check to see if the coolant is low, and maybe do a compression test, the head gasket might be bad

common problem on this model

Answer 2

P0300 NISSAN - Cylinder Misfire Detected Random Cylinders

Read more: https://www.autocodes.com/p0300_nissan.html