Engine & Drivetrain
I have a 2009 CXL w/125K mi.
Suddenly, I have CEL on, CODES PO: 300
Literally one moment it's running fine. Come out of the store and have 3 cylinders misfiring.
I thought changing spark plugs would help but, then I thought why 1,3,&4 only. Why not the others? Why suddenly?