The Lemon IndexCylinder 3 is not firing properly, so the engine runs rough and loses some power. Full P0303 page
20 owner complaints · the #1 code Honda Accord owners name · 10% of Honda Accord complaints that name a code (every car: 2.4%)
Middle of 94,000 miles · most between 90,000 and 101,000 (8 owners gave it)
Honda Accord owners named P0303 in 20 complaints to the U.S. government (NHTSA), most often on the 2018, 2019 and 2010 model years, at a middle of 94,000 miles. The part they name most is the spark plugs (6 complaints). Complaints are owner reports, not proof of a defect.
Honda Accord model years that report P0303
Owner complaints naming P0303, by model year. Raw counts: years that sold more get more complaints, so this is each model year's record, not a failure rate.
Mileage when it happened
94,000 miles is the middle of what 8 owners entered. Half were between 90,000 and 101,000 miles.
The mileage on the complaint form, when the owner gave one.
What owners say caused it or fixed it
The most-named part is the spark plugs, in 6 of the 20 complaints (30%). 5 of those mention it being replaced or repaired, and 2 say the problem came back afterwards. Next: head gasket (6), engine software (a reflash) (3) and turbocharger or wastegate (3).
- Spark plugs6 complaints5 mention a repair or replacement, 2 of them say the problem came back · what Honda Accord owners paid
- Head gasket or coolant in a cylinder6 complaints3 mention a repair or replacement · what Honda Accord owners paid
- Software update (reflash)3 complaints3 mention a repair or replacement, 2 of them say the problem came back
- Turbocharger or wastegate3 complaints1 mentions a repair or replacement, 1 of them says the problem came back · what Honda Accord owners paid
- Fuel injectors2 complaints1 mentions a repair or replacement · what Honda Accord owners paid
8 complaints mention a recall and 5 mention a warranty.
Counted from the owners' own words: a part counts when a sentence names it with a cause or repair word. What owners wrote, not a diagnosis. A shop should confirm the cause before replacing parts.
Symptoms owners describe with P0303
45% of these complaints say the check engine light came on.
- Shakes, runs rough or misfires85%17 of 20 complaints
- Loses power or goes into limp mode45%9 of 20 complaints
- Stalls or shuts off30%6 of 20 complaints
- Warning lights and electrical faults30%6 of 20 complaints
- Overheats20%4 of 20 complaints
- Brakes or ABS act up15%3 of 20 complaints
Share of the complaints naming P0303 whose text also describes each problem. A complaint can describe more than one.
Codes owners report with it
P0302 7 P0300 5 P0304 3 P0301 2 P0299 2
Other codes named in the same Honda Accord complaints, and in how many.
Repair costs
Honda Accord spark plug replacement cost · Honda Accord head gasket replacement cost · Honda Accord turbocharger replacement cost · Honda Accord fuel injector replacement cost
Recalls on these Honda Accord years
- Transmission & drivetrain · 2008, 2009, 2010 · issued 2011
HONDA IS RECALLING CERTAIN MODEL YEAR 2005-2010 ACCORD, 2007-2010 CR-V, AND 2005-2008 ELEMENT PASSENGER CARS MANUFACTURED FROM JULY 1, 2004, THROUGH SEPTEMBER 3, 2010. NHTSA 11V395000
1 recall for the same systems (engine and powertrain) on the Honda Accord model years above. A recall for the same system isn't proof it's behind P0303. Recall work is free at any dealer: check a VIN at nhtsa.gov/recalls or with our VIN check.
Keep going
- P0303: meaning, causes and every car that reports it
- Honda Accord reliability by year
- 2018 Honda Accord problems and recalls
Other codes Honda Accord owners report
P0304 P0301 P0302 P0300 P0087 P0741
P0303 on other cars
Ford Escape (62) · Ford Edge (34) · Chrysler Pacifica (26) · Honda CR-V (23) · Ford Fusion (22) · Honda Odyssey (16) · Kia Soul (14)
The details
How we count
We read every owner complaint in the NHTSA file whose text names this trouble code, and count the ones filed about this model (matched by the make, model and model year on the complaint). Mileage is what the owner entered on the form.
Parts: a complaint counts for a part when one of the owner's own sentences names that part together with a cause word (failed, bad, diagnosed, caused by, leaking ...) or a repair word (replaced, repaired, new, reprogrammed ...). "Came back" means the same complaint also says the problem returned or the repair didn't fix it. These are counts of what owners wrote, not a diagnosis, and one complaint can name several parts.
Complaints are reports, not proof of a defect, and most owners never file one. Popular models get more complaints, so the counts are not a failure rate. The code meaning is the standard SAE J2012 definition in our own words, or the carmaker's meaning where we verified it for that make.
What P0303 means
Cylinder 3 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.
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 3
- Fuel injector on cylinder 3
- Vacuum leak near that cylinder
- Low compression (valve or piston ring problem)
Check the complaints yourself
NHTSA complaint numbers (search them at nhtsa.gov): 11762909, 11762060, 11753271, 11747924, 11745437, 11745174, 11736450, 11731442, 11720728, 11693827, 11655914, 11591398 and 8 more.
Quick answers
What does P0303 mean on a Honda Accord?
Cylinder 3 Misfire Detected. Cylinder 3 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.
Which Honda Accord years have the most P0303 complaints?
In complaints to NHTSA, owners of the 2018 (9), 2019 (3), 2010 (2) Honda Accord named P0303 most (20 complaints in all, 2000–2024). Raw counts, not a failure rate.
What fixes P0303 on a Honda Accord?
Owners most often name the spark plugs (6 of 20 complaints), then head gasket and engine software (a reflash). That's what owners wrote, not a diagnosis: have a shop confirm the cause with a scan and tests before replacing parts.
At what mileage does P0303 show up on a Honda Accord?
Owners who gave their mileage reported a middle of 94,000 miles; half were between 90,000 and 101,000 (8 owners).
Can I drive my Honda Accord with P0303?
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.
Sources: NHTSA owner complaints that name P0303 on the Honda Accord, counted by The Lemon Index; NHTSA recalls; repair bills owners named. Meanings: SAE J2012 in our own words. Owner reports, not a diagnosis or repair advice for your car.