P0304 - CYLINDER 4 MISFIRE DETECTED

Basically, the diagnostic code P0304 OBD2 indicates that a misfire has been detected. This fault originates specifically in the cylinder number 4. It should be noted that, together with this code, codes related to misfire can be established.

The ECM (Engine Control Module) constantly monitors the proper functioning of all cylinders to ensure that everyone is firing in time.

• Check Engine light turns on.
• An unstable motor.
• The engine loses power.
• There are entry leaks.
• Lower fuel consumption.

The reasons why the fault code P0304 OBD II can be established are:

• Low fuel level.
• Components of the vehicle ignition system such as spark plugs or, its wires could be defective. Likewise, the coil may be defective.
• Oxygen sensor (O2) may be defective.
• Faulty fuel injector.
• Catalytic Converter (TWC) failures.
• There may be bad compression.

To solve all the problems caused by the DTC code P0304 you could do the following:

• If the motor is unstable, you should check the entire cable system as well as its connectors that lead to the cylinders. Take into account that ignition components - such as spark plugs, spark plug wires, distributor cap - need to be replaced over time, as they deteriorate due to use.
• If you notice a strange smell coming from the exhaust, it may mean that the Three-Way Catalyst (TWC) is having problems. That's why you can change the cat.
• One of the fuel injectors may be defective, repaired or changed if necessary.