P0304 Cylinder 4 Misfire Detected
Technical Description
Cylinder #4 Misfire Detected
What does that mean?
This diagnostic trouble code (DTC) is a generic powertrain code, which means that it applies to OBD-II equipped vehicles. Although generic, the specific repair steps may vary depending on make/model.
A P0304 code means that the the car’s computer has detected that one of the engine’s cylinders is not firing properly. In this case it’s cylinder #4.
Symptoms
Causes
Possible Solutions
If there are no symptoms, the simplest thing to do is to reset the code and see if it comes back.
If there are symptoms such as the engine is stumbling or hesitating, check all wiring and connectors that lead to the cylinders (i.e. spark plugs). Depending on how long the ignition components have been in the car, it may be a good idea to replace them as part of your regular maintenance schedule. I would suggest spark plugs, spark plug wires, distributor cap, and rotor (if applicable). Otherwise, check the coils (a.k.a. coil packs). In some cases, the catalytic converter has gone bad. If you smell rotten eggs in the exhaust, your cat converter needs to be replaced. I’ve also heard in other cases the problems were faulty fuel injectors.
Other Reading
P0300 – Random/Multiple Cylinder Misfire Detected
Need help?
Let us fix your problem. You are most welcome our diagnosis experts have in most cases the knowledge and skills to find the cause of the error code p0304 and to solve the problems.
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"Delete Error Code Permanently, Disable DTC Error Code Function for p0304 in the ECU"
In extreme cases, we even have the option to permanently remove the specific DTC p0304 and disable the function of the specific error code in the ECU. All other fault code functions will then continue to work to protect the engine. This is different from clearing an error code with a diagnostic device. We have the option to permanently remove the function of the specific error code, so that it never comes back. Also emergency running that occurs on the specific error code can be solved in most cases.
Of course we prefer to first try to solve the cause of the error code, but sometimes the only solution is to permanently disable the DTC function of p0304.
