P0301 Cylinder 1 Misfire Detected
Cylinder 1 is misfiring – the fuel in it isn't burning properly.
Common causes
- Worn spark plug or failing ignition coil on cylinder 1
- Leaking or clogged fuel injector
- Low compression (valves, rings, head gasket)
Symptoms
- Rough idle, shaking, hesitation
- The check engine light may flash
Can I drive with it?
Drive gently and get it fixed soon. If the light flashes, slow down and stop driving as soon as you safely can.
Tip: A classic test: swap the cylinder 1 coil with a neighbour's, clear the code and drive. If the misfire moves, the coil is bad.
Which scanner reads it?
Any OBD2 scanner reads it.
Budget tools like the ANCEL AD310 read it; tools with live data and graphing – like the BlueDriver or OBDLink MX+ – help you find the cause. Not sure which fits you? Try the Find My Scanner quiz.
In the data
How common is it? At New York’s emissions inspections in 2020–21, P0301 was the #10 code found on cars that failed – 1.7% of all the codes found.
Of the vehicle complaints owners filed with NHTSA from 2015 to 2025, 244 quote P0301 – most often from Ford, Honda, Hyundai owners. Complaints lean toward serious problems, so treat this as a sign of how often the code turns up in real reports, not how often cars get it.
Both sources are compared on the Trends page.
Related codes
General information to help you understand a code – not a diagnosis. Your car’s service information or a qualified mechanic has the final word. See how we research.