Diagnostic Trouble Code
P0300 — Random/Multiple Cylinder Misfire
Random/Multiple Cylinder Misfire
Definition
The ECM has detected random or multiple cylinder misfires. Unlike single-cylinder codes (P0301–P0308), P0300 indicates the misfire pattern is not isolated to one cylinder, suggesting a systemic cause affecting the entire engine.
Common Causes
- Worn spark plugs or ignition coils
- Vacuum leak affecting multiple cylinders
- Low fuel pressure or failing fuel pump
- Clogged EGR valve or stuck-open EGR
- Compression loss across multiple cylinders (head gasket, valve issues)
- Contaminated fuel