P0300 Chevrolet -

Question

I have a p0300 code. I have changed plugs, wires, coils, crankshaft sensor, and had the fuel injectors cleaned professionally. I'm going crazy trying to figure this out. Any help??

Answer 1

HI there,

Check for intake manifold leaks and any other vacuum leak. You may also have to check the engine compression or do a leak down test. Basically the computer knows there is a misfire but doesn't know which cylinder. Also, check the catalytic converter. If it's plugging up it can send back pressure into the engine and cause a misfire code.