SES Light And/Or Engine Misfires On All Cylinders - Inspect Ground - keywords - compression controls damage detonation dtc gt knock low mil no P0300 P0301 P0302 P0303 P0304 P2261 ping plug power

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

On rare occasion, various engine performance issues, such as engine misfires, SES light, no power, and/or detonation may be experienced. This may be the result of a loose engine ground on the left front of the cylinder head. If the customer continues to drive the vehicle like this, the concern will get more severe, and engine/spark plug damage may occur. Upon inspection, DTCs P0300, P0301, P0302, P0303, P0304, and/or P2261 may be stored.

If the SI diagnosis does not isolate a cause for this concern, inspect the ground that is on the left front of the cylinder head to see if it is loose or corroded, and repair it as necessary. If a poor ground is found, remove the spark plugs and inspect them for fouling, damage, etc. If a spark plug concern is found, replace them and re-evaluate the concern.

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.