Code No. P0304: No. 4 Cylinder Injector Malfunction (No Injection)




FUNCTION



  • The Engine-ECU, by monitoring the variation in the engine revolution, detects the non-fuel injection state.

TROUBLE JUDGMENT


Check Conditions
  • During the normal engine operation
  • Engine coolant temperature is 80°C or higher.
  • Crank angle sensor is normal.
Judgment Criterion
  • The variation in the engine revolution is more than the specified value.

PROBABLE CAUSES



  • Failed No. 4 injector
  • No. 4 fuel injection pipe clogged
  • Failed Engine-ECU

DIAGNOSIS PROCEDURE


caution A high-tension voltage is flowing between the engine-ECU and the injectors while the engine is running. Handle them carefully to avoid receiving electric shocks from the voltage.

STEP 1. M.U.T.-III diagnosis code



  • After erasing the diagnosis code through M.U.T.-III, operate the engine in the warm-up state and confirm and confirm whether the diagnosis code is output

Q. Is the diagnosis code set?

Go to Step 2 .
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).

STEP 2. Check for No.4 fuel injection pipe clogged



  • Remove the No. 4 fuel injection pipe.
  • Check whether No.4 fuel injection pipe is clogged or not.

Q. Is it clogged?

Clean or replace the No. 4 fuel injection pipe.
Replace the No. 4 injector. After replacing the injector, register the injector identification code and learn fuel injection (Refer to GROUP 00 - Precautions Before Service - What The Common Rail Engine Learns ). Then go to Step 3 .

STEP 3. M.U.T.-III diagnosis code



  • After erasing the diagnosis code through M.U.T.-III, operate the engine in the warm-up state and confirm and confirm whether the diagnosis code is output.

Q. Is the diagnosis code set?

Replace the engine-ECU. When the engine-ECU is replaced, write the chassis number (Refer to GROUP 00 - How to Perform Chassis Number Writing ). After replacing the engine-ECU, register the injector identification code and learn fuel injection (Refer to GROUP 00 - Precautions Before Service - What The Common Rail Engine Learns ).
The check is end.