Originally Posted by romeo
P0300 Random/Multiple Cylinder Misfire Detected
P0301 Cylinder 1 Misfire Detected
P0302 Cylinder 2 Misfire Detected
P0303 Cylinder 3 Misfire Detected
P0304 Cylinder 4 Misfire Detected
What about P0399?
The misfires would be fixed with new spark plugs and wires, so the problem is probably that last unknown code.