P0304 Cylinder 4 – Ignition loss detected
DTC code description P0304 General
This DTC code is general for the propulsion system and therefore applies to vehicles equipped with ODB-II. In principle, this code indicates that the vehicle’s computer ECM (engine control unit) has detected that one of the cylinders of the engine is not functioning correctly. In this case, it means that the fault is in cylinder 4.
Symptoms of DTC code P0304 General
- There are problems when starting the engine
- Uneven work
- The engine shakes and interrupts
- Loss of power during vehicle acceleration
- Smell the petrol
- Black smoke coming out of the exhaust pipe
Cause of DTC code P0304 General
Code P0304 may have one or more of the following problems:
- The spark plug or cable is damaged.
- Ignition coil.
- One or both oxygen sensors may be in poor condition.
- The fuel injector may fail.
- Exhaust valve is burned.
- Catalyst is faulty.
- Fuel tank’s empty.
- Poor compression
- The ECM module may be damaged.
Possible solutions for DTC code P0304 General
To repair DTC code P0304, you can check the following components:
Check all cables and their connectors that lead to the cylinders.
Check that the spark plugs, cables, distributor hood, etc., are not damaged. They function properly.
Perform maintenance on spark plugs and cables and replace them if necessary.
Check the coil.
Examine the fuel injectors and clean with a dedicated nozzle cleaner.
Check the air mass flow sensor.
Check EGR (Exhaust Gas Recirculation) valve as it may be open.
Check the compression in the engine and that there are no vacuum leaks.