Engine and gearbox (P)
P0301: Cylinder 1 misfire
A misfire in cylinder 1 indicates that the cylinder is not firing correctly. This can be due to ignition, fuel, or compression issues.
Checked by a licensed car technician · last reviewed 29 September 2026
Symptoms
- Rough idle
- Engine hesitation
- Reduced power
- Increased fuel consumption
Common causes
- Bad spark plug
- Failed ignition coil
- Clogged fuel injector
- Low compression
- Vacuum leak
How to check it yourself
- Inspect spark plug in cylinder 1
- Test ignition coil for cylinder 1
- Check fuel injector for cylinder 1
- Perform a compression test on cylinder 1
- Inspect for vacuum leaks around cylinder 1
Can I keep driving?
The car can be driven, but prolonged driving may cause damage to the catalytic converter.
General guidance, not a professional inspection. Confirm faults with measurements before buying parts, and use a qualified mechanic for brakes, steering, fuel leaks, airbags, and other safety-critical work. Terms and disclaimer