My 2001 Galant 2.4L is giving me a P0300 various misfire error, about a week ago I changed the plugs and wires and notice some oil in the pistol #4 spark plug well. SES light was on but went off for a day after the tune up then re appeared. Next day I changed the coil and oil well gaskets, again SES light went away then came back a week later. Today I changed plugs, coils, wires again and SES light still on with a P0300 code, any suggestions???

 

??? anyone

 

you probably have a bad ground wire, either the coil pack grounds or fuel injector grounds, those are usually located on the right side of the head (4g64 engine)