Lancer Ralliart Sportback 0300, stumped, next step?

Question

Getting the 0300 code. Engine hesitates etc. Mechanic replaced valve cover gasket and coils. Slightly better but still coding. If compression OK what is next step? Fuel pressure? Sensor replacement? mechanic stumped, I feel like I'm throwing $ at the problem and not solving. Appreciate any insight!

Answer 1

Hi there

If the compression is ok, then I would check the mass air flow sensor and check for vacuum leaks on the engine. If none are found, then the next step would be the fuel pressure.