The Lemon IndexCylinder 9 is not firing properly, so the engine runs rough and loses some power.
Get it fixed soon. A few more days of normal driving is usually OK, but waiting can turn a small repair into a bigger one or a breakdown.
Spark plug or ignition coil on cylinder 9. Then: fuel injector on cylinder 9; vacuum leak near that cylinder.
Owners named P0309 in 5 complaints to the U.S. government, most often on the Nissan Altima.
Cars owners report it on
Complaints that name P0309, by model. Raw counts, not a failure rate: popular models get more complaints.
Years owners report it on most: 2009 Nissan Altima
The details
What P0309 means
Cylinder 9 is not firing properly, so the engine runs rough and loses some power. A flashing check engine light means the misfire is serious enough to damage the catalytic converter, so slow down and get it checked right away.
Can I drive with P0309?
Get it fixed soon. A few more days of normal driving is usually OK, but waiting can turn a small repair into a bigger one or a breakdown.
40% of the owner complaints that name P0309 also say the car won't start or hard to start. A complaint can describe more than one problem, so this doesn't prove the code caused it.
Common causes of P0309
- Spark plug or ignition coil on cylinder 9
- Fuel injector on cylinder 9
- Vacuum leak near that cylinder
- Low compression (valve or piston ring problem)
A shop should confirm the cause with a scan and tests before replacing parts.
What owners describe
- Won't start or hard to start: 40% of complaints
Share of complaints naming the code whose text also mentions each problem.
Model years that report P0309 most
2009 Nissan Altima (2).
Related codes
P0308 P0307 P0306 P0305 P0304 P0303 P0302 P0301
Quick answers
What does P0309 mean?
Cylinder 9 Misfire Detected. Cylinder 9 is not firing properly, so the engine runs rough and loses some power. A flashing check engine light means the misfire is serious enough to damage the catalytic converter, so slow down and get it checked right away.
Can I drive with P0309?
Get it fixed soon. A few more days of normal driving is usually OK, but waiting can turn a small repair into a bigger one or a breakdown.
What causes P0309?
Spark plug or ignition coil on cylinder 9; Fuel injector on cylinder 9; Vacuum leak near that cylinder; Low compression (valve or piston ring problem).
Counts: NHTSA owner complaints whose text names P0309. A complaint is an owner's report, not a diagnosis. Meanings: the standard SAE J2012 definitions in our own words; manufacturer codes only where verified for that make. General information, not repair advice for your car.