P0304 on JEEP WRANGLER — Cylinder 4 Misfire Detected

Q: "What does P0304 mean on a JEEP WRANGLER?"

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

Q: "What are the most common causes of P0304 on JEEP WRANGLER?"

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

Q: "Is P0304 serious on my JEEP WRANGLER?"

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

Q: "What should I do if my JEEP WRANGLER 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 JEEP WRANGLER

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 JEEP WRANGLER owners have reported this issue to NHTSA across model years 2013-2018. Most reports come from the 2015, 2013 model years. The most commonly reported component is Engine (71.4% of reports).

Real JEEP WRANGLER Owner Reports

Source: NHTSA Complaints Database

"Brought 2013 wrangler to dealer for constant p0304 code after replacing ignition coils and spark plugs. dealer did a compression leak test to verify that the 4th cylinder head was bad and need replacing and will cost $3700.00 for the repair."

— 2013 JEEP WRANGLER owner · ENGINE · Filed 01/14/2021

"P0302 misfire cylinder 2. p0300, p0304 & p0306 jeep/dodge is very aware of this cylinder issue and has a service bulletin for several models. (journey, wrangler, 200/avenger, challenger, charger, grand caravan, durango and grand cherokee). and they will not recall this part."

— 2013 JEEP WRANGLER owner · ENGINE · Filed 11/12/2018

"2015 original owner, developed misfire cylinder #4 P0304, replaced coils, plugs, injectors, harness on that side. Misfire still present, noted others have reported issues with cylinder head (valves, cams, rockers)."

— 2015 JEEP WRANGLER owner · ENGINE · Filed 09/30/2024

"I have experience a complete loss of control of the vehicle on both highways and streets that are bumpy due to dips, potholes, rough conditions due to the road."

— 2015 JEEP WRANGLER owner · UNKNOWN OR OTHER,ENGINE,FUEL/PROPULSION SYSTEM · Filed 07/09/2023

"My 2015 Jeep Wrangler with 80,200 developed the well know Pentastar Tick. The Jeep would misfire at idle when slowing to a stop light. The check engine light came on and the code was a P0304. I'm the original owner and took it to the dealer I purchased it from."

— 2015 JEEP WRANGLER owner · ENGINE · Filed 10/08/2021

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

📊 Complaint Trend by Model Year

2

'13

4

'15

1

'18

Common Causes on JEEP WRANGLER

Based on NHTSA complaint component analysis for this vehicle.

ENGINE 71.4%

UNKNOWN or OTHER,ENGINE,FUEL/PROPULSION SYSTEM 14.3%

POWER TRAIN,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 JEEP WRANGLER? ▾

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

What are the most common causes of P0304 on JEEP WRANGLER? ▾

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

Is P0304 serious on my JEEP WRANGLER? ▾

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

What should I do if my JEEP WRANGLER 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.