P0304 on HONDA ODYSSEY — Cylinder 4 Misfire Detected

Q: "What does P0304 mean on a HONDA ODYSSEY?"

"P0304 indicates: Cylinder 4 Misfire Detected. This is a ignition system code. 16 HONDA ODYSSEY owners have reported this to NHTSA."

Q: "What are the most common causes of P0304 on HONDA ODYSSEY?"

"Based on 16 NHTSA reports, the most commonly cited components are: Engine, Power Train,Engine, Power Train,Unknown Or Other,Engine. These percentages are based on the component field in owner complaints."

Q: "Is P0304 serious on my HONDA ODYSSEY?"

"Of 16 NHTSA reports for this code on HONDA ODYSSEY, none involved a crash or fire. However, any diagnostic code should be evaluated by a qualified mechanic."

Q: "What should I do if my HONDA ODYSSEY shows P0304?"

"1) Check for recalls on your VIN at nhtsa.gov/recalls. 2) Get a professional diagnosis — a code alone doesn't identify the exact failed part. 3) Get 2-3 repair estimates to compare."

What P0304 Means on Your HONDA ODYSSEY

P0304 is a diagnostic trouble code indicating: Cylinder 4 Misfire Detected. This code relates to the ignition system system. The vehicle's computer detected a condition outside normal operating parameters and stored this code.

16 HONDA ODYSSEY owners have reported this issue to NHTSA across model years 2012-2016. Most reports come from the 2013, 2015 model years. The most commonly reported component is Engine (62.5% of reports).

Real HONDA ODYSSEY Owner Reports

Source: NHTSA Complaints Database

"For several years now, we have misfire issue or code P0304. We continue to change spark plugs cylinders. Both usually last a year or so then they need replaced again. I research the problem, no recall or the like."

— 2012 HONDA ODYSSEY owner · ENGINE · Filed 08/02/2025

"Dear NHTSA Advisor, Thank you for regarding my request for warranty coverage for the critical misfire and overheating defect with my 2012 Odyssey Honda Engine 3.5L Engine. Odyssey, as described in Honda’s Service Technical Bulletin 13-081."

— 2012 HONDA ODYSSEY owner · POWER TRAIN,UNKNOWN OR OTHER,ENGINE · Filed 08/05/2025

"This vehicle began using oil and the mechanic I took it to told me that the piston rings were compromised."

— 2013 HONDA ODYSSEY owner · ENGINE · Filed 08/11/2025

"I’m reporting a repeat engine misfire on my 2013 Honda Odyssey (P0303 – cylinder 3). Honda repaired this issue in 2018 under Service Bulletin 13-081, which followed the Soto v. Honda settlement. Now in 2025, the exact same failure has returned—same code, same cylinder, same symptoms."

— 2013 HONDA ODYSSEY owner · POWER TRAIN,ELECTRICAL SYSTEM,ENGINE · Filed 06/25/2025

"Engine backfired and failed at 125000 going 60 mph on major highway. Mechanic found the problem to be with the pistons, rings, oil and the vehicle's continues system to reduce miles per gallon of gas system. He replaced rings and pistons."

— 2013 HONDA ODYSSEY owner · ENGINE · Filed 02/02/2024

All reports filed by vehicle owners directly with the U.S. Department of Transportation.

📊 Complaint Trend by Model Year

2

'12

8

'13

2

'14

3

'15

1

'16

Common Causes on HONDA ODYSSEY

Based on NHTSA complaint component analysis for this vehicle.

ENGINE 62.5%

POWER TRAIN,ENGINE 12.5%

POWER TRAIN,UNKNOWN or OTHER,ENGINE 6.2%

POWER TRAIN,ELECTRICAL SYSTEM,ENGINE 6.2%

POWER TRAIN 6.2%

What To Do Next

1
Check for recalls on YOUR VIN
Go to nhtsa.gov/recalls and enter your VIN. If your vehicle is covered, repairs are free.
2
Get a proper diagnosis
A code alone doesn't tell you the exact failed part. A diagnostic at a shop ($50–$150) pinpoints the root cause before you spend money on parts.
3
Compare repair quotes
Get 2–3 quotes. Dealer vs. independent shop prices often differ 30–50% for the same repair.

Frequently Asked Questions

What does P0304 mean on a HONDA ODYSSEY? ▾

P0304 indicates: Cylinder 4 Misfire Detected. This is a ignition system code. 16 HONDA ODYSSEY owners have reported this to NHTSA.

What are the most common causes of P0304 on HONDA ODYSSEY? ▾

Based on 16 NHTSA reports, the most commonly cited components are: Engine, Power Train,Engine, Power Train,Unknown Or Other,Engine. These percentages are based on the component field in owner complaints.

Is P0304 serious on my HONDA ODYSSEY? ▾

Of 16 NHTSA reports for this code on HONDA ODYSSEY, none involved a crash or fire. However, any diagnostic code should be evaluated by a qualified mechanic.

What should I do if my HONDA ODYSSEY shows P0304? ▾

1) Check for recalls on your VIN at nhtsa.gov/recalls. 2) Get a professional diagnosis — a code alone doesn't identify the exact failed part. 3) Get 2-3 repair estimates to compare.