The engine computer tracks current flow during the glow plug heating phase. If the current draw on cylinder 9 is mismatching the other cylinders, this code triggers. This occurs when the plug has degraded or you install an incorrect replacement part. Always replace plugs with matching resistance specs to prevent feedback errors.
Mechanic Glossary
9 Glow Plug Incorrect
A fault indicating that current draw or resistance from the cylinder 9 glow plug is outside standard limits.
Frequently Asked Questions
The engine computer detected abnormal current draw from cylinder 9 glow plug during the pre-heat cycle.
Yes, but make sure the replacement plug has the exact same voltage and resistance specs as the other plugs.
Yes. Once the computer detects the correct current draw during a few start cycles, the code will clear.