Common Checks
- Inspect the cylinder 1 spark plug, coil, boot, and injector connector.
- Move the coil or plug to another cylinder to see whether the misfire follows.
- Check compression if ignition and fuel tests pass.
Diagnostic trouble code
P0301 Cylinder 1 Misfire Detected
The PCM detects a misfire on cylinder 1.
Misfire CodesCommon Repairs
- Replace the failed plug, coil, boot, wire, or injector identified by swap testing.
- Repair wiring or mechanical faults if the misfire does not follow ignition parts.
Mustang Notes
- Cylinder numbering depends on engine family; verify before moving parts.
Model-Year Applicability
Listed for 1996 and newer traditional gasoline Mustang pages in this first-pass catalog. Engine, calibration, and Ford-specific codes may narrow that range as more service data is added.