P0304 on HONDA FIT — Cylinder 4 Misfire Detected

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

"P0304 indicates: Cylinder 4 Misfire Detected. This is a ignition system code. 7 HONDA FIT owners have reported this to NHTSA."

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

"Based on 7 NHTSA reports, the most commonly cited components are: Fuel/Propulsion System, Engine,Fuel/Propulsion System, Engine. These percentages are based on the component field in owner complaints."

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

"Of 7 NHTSA reports for this code on HONDA FIT, 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 FIT 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 FIT

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.

7 HONDA FIT owners have reported this issue to NHTSA across model years 2018-2019. Most reports come from the 2019, 2018 model years. The most commonly reported component is Fuel/Propulsion System (42.9% of reports).

Real HONDA FIT Owner Reports

Source: NHTSA Complaints Database

"This is after the recall on 2018-19 Fit Carbon Buildup with Misfire DTCs under codes P0300-P0304) and after fuel injectors are replaced. Current problem is with combination of carbon deposits on intake valves. Failing fuel injector/s causing an incorrect air/fuel ratio with code under P0172."

— 2018 HONDA FIT owner · ENGINE · Filed 09/03/2025

"Car is not running properly. Idling very poorly. Check engine light is on. Check engine light code is P0300, P0301, P0304. Honda has issued extended warranty for the same make/model(2018 Honda fit). My car's VIN is not included. Spoke with Honda corporate. No explanation for this."

— 2018 HONDA FIT owner · FUEL/PROPULSION SYSTEM · Filed 05/14/2024

"At 74k miles my check engine light came on randomly. Took the car to a mechanic, who turned the light off and advised me to tighten the gas cap. A few weeks later the check engine light came back on. Auto zone said a spark plug needed replacement."

— 2018 HONDA FIT owner · ENGINE,FUEL/PROPULSION SYSTEM · Filed 10/03/2023

"Four dashboard warning signs (Check Engine Light, Tire Pressure Monitoring System, Vehicle Stability Assist System, Electric Power Steering) appeared all at once suddenly. I had the vehicle towed to my local Honda dealership for service."

— 2019 HONDA FIT owner · FUEL/PROPULSION SYSTEM · Filed 11/01/2024

"All warning lights cycle through on vehicle dashboard after turning on vehicle. Vehicle was taken to Honda Auto Service Center, where issue is diagnosed as Carbon Buildup, causing misfires. Error Diagnostic Code is one of P0300 - P0304. After maintenance, error clears out."

— 2019 HONDA FIT owner · ENGINE,FUEL/PROPULSION SYSTEM · Filed 02/14/2025

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

📊 Complaint Trend by Model Year

3

'18

4

'19

Common Causes on HONDA FIT

Based on NHTSA complaint component analysis for this vehicle.

FUEL/PROPULSION SYSTEM 42.9%

ENGINE,FUEL/PROPULSION SYSTEM 42.9%

ENGINE 14.3%

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 FIT? ▾

P0304 indicates: Cylinder 4 Misfire Detected. This is a ignition system code. 7 HONDA FIT owners have reported this to NHTSA.

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

Based on 7 NHTSA reports, the most commonly cited components are: Fuel/Propulsion System, Engine,Fuel/Propulsion System, Engine. These percentages are based on the component field in owner complaints.

Is P0304 serious on my HONDA FIT? ▾

Of 7 NHTSA reports for this code on HONDA FIT, none involved a crash or fire. However, any diagnostic code should be evaluated by a qualified mechanic.

What should I do if my HONDA FIT 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.