P0304: Cylinder 4 misfire detected

What does it mean?

System

Powertrain (engine and transmission)

Subsystem

Ignition and misfires

Type of code

Generic code: means the same on every make.

How urgent?

Do not drive further than you need to: carrying on can damage the engine, the catalyst or other parts. If the engine light is flashing, stop safely as soon as you can.

Possible causes

• Worn spark plugs
• Faulty ignition coil or lead
• Injector not spraying correctly
• Mechanical: low compression, valve or gasket

Tip: don’t just clear the code. Clearing a code doesn’t fix the cause. It often comes back, and the stored data that helps us find the cause is then gone.