Jeep P0304 Error Code: How to Fix It

Q: Can I drive my Jeep with P0304 code?

You can drive short distances to a repair facility, but avoid extended driving. Continued driving with a cylinder 4 misfire can damage the catalytic converter, cause poor fuel economy, and potentially lead to more expensive engine repairs.

Q: How much does it cost to fix P0304 in a Jeep?

Repair costs vary widely depending on the root cause. Simple fixes like spark plugs cost $20-60, while ignition coils range from $50-150. Fuel injector replacement can cost $150-400, and major internal engine problems can run $1500-4000 or more.

Q: What causes P0304 misfire in Jeep vehicles?

Common causes include faulty spark plugs, bad ignition coils, clogged fuel injectors, vacuum leaks, low compression from worn engine components, timing issues, or fuel delivery problems. Jeeps are also known for ignition coil failures, especially in higher mileage vehicles.

Q: Will P0304 clear itself?

P0304 may temporarily clear if you reset the codes, but it will return if the underlying problem isn't fixed. The engine control module continuously monitors cylinder performance, so misfires will be detected and the code will reappear during normal driving.

Q: How do I know if it's the spark plug or ignition coil?

Swap the spark plug and ignition coil from cylinder 4 with those from other cylinders. If the misfire moves to the new cylinder, the component you swapped is faulty. If the misfire stays in cylinder 4, look for other causes like fuel injector problems or internal engine issues.

Abstract

The P0304 error code indicates that your Jeep's engine control module has detected a misfire in cylinder 4. This means the fuel and air mixture in cylinder 4 isn't burning properly, which can cause rough idling, reduced power, and potential engine damage if left unaddressed.