P0304 on HYUNDAI TUCSON — Cylinder 4 Misfire Detected

Q: "What does P0304 mean on a HYUNDAI TUCSON?"

"P0304 indicates: Cylinder 4 Misfire Detected. This is a ignition system code. 3 HYUNDAI TUCSON owners have reported this to NHTSA."

Q: "What are the most common causes of P0304 on HYUNDAI TUCSON?"

"Based on 3 NHTSA reports, the most commonly cited components are: Engine, Fuel/Propulsion System. These percentages are based on the component field in owner complaints."

Q: "Is P0304 serious on my HYUNDAI TUCSON?"

"Of 3 NHTSA reports for this code on HYUNDAI TUCSON, none involved a crash or fire. However, any diagnostic code should be evaluated by a qualified mechanic."

Q: "What should I do if my HYUNDAI TUCSON 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 HYUNDAI TUCSON

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.

3 HYUNDAI TUCSON owners have reported this issue to NHTSA across model years 2016-2022. Most reports come from the 2016, 2017 model years. The most commonly reported component is Engine (66.7% of reports).

Real HYUNDAI TUCSON Owner Reports

Source: NHTSA Complaints Database

"My 2016 Hyundai Tucson has had power and acceleration issues since I purchased it brand new in 2016 from the dealership. When trying to accelerate onto the freeway, or trying to turn onto busy traffic the engine would rev but not pick up speed causing a dangerous situation when traffic is present."

— 2016 HYUNDAI TUCSON owner · ENGINE · Filed 03/26/2024

"My 2017 Hyundai Tucson 1.6 liter is experiencing severe engine issues that closely mirror those subject to recent class action lawsuits. The engine exhibits excessive oil consumption. I have experienced a sudden loss of power on roadways in traffic as well as on the highway."

— 2017 HYUNDAI TUCSON owner · ENGINE · Filed 07/14/2025

"The first incident was on 5/27/24 when I was traveling about 45 mph. The check engine light came on and the car started to shimmy and shake when I pressed the gas. Error code came up on the screen for P0304, injector #4 was bad."

— 2022 HYUNDAI TUCSON owner · FUEL/PROPULSION SYSTEM · Filed 07/16/2024

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

📊 Complaint Trend by Model Year

1

'16

1

'17

1

'22

Common Causes on HYUNDAI TUCSON

Based on NHTSA complaint component analysis for this vehicle.

ENGINE 66.7%

FUEL/PROPULSION SYSTEM 33.3%

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 HYUNDAI TUCSON? ▾

P0304 indicates: Cylinder 4 Misfire Detected. This is a ignition system code. 3 HYUNDAI TUCSON owners have reported this to NHTSA.

What are the most common causes of P0304 on HYUNDAI TUCSON? ▾

Based on 3 NHTSA reports, the most commonly cited components are: Engine, Fuel/Propulsion System. These percentages are based on the component field in owner complaints.

Is P0304 serious on my HYUNDAI TUCSON? ▾

Of 3 NHTSA reports for this code on HYUNDAI TUCSON, none involved a crash or fire. However, any diagnostic code should be evaluated by a qualified mechanic.

What should I do if my HYUNDAI TUCSON 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.