LEMON Manuals: Even more car manuals for everyone
Home >> Honda >> 2012 >> Fit Base, Automatic Trans >> Repair and Diagnosis >> Engine Performance >> System >> PGM-FI System >> DTC Troubleshooting >> DTC P0301, P0302, P0303, P0304: No. 1 Cylinder Misfire Detected; No. 2 Cylinder Misfire Detected; No. 3 Cylinder Misfire Detected; No. 4 Cylinder Misfire Detected ('09-10)

DTC P0301, P0302, P0303, P0304: No. 1 Cylinder Misfire Detected; No. 2 Cylinder Misfire Detected; No. 3 Cylinder Misfire Detected; No. 4 Cylinder Misfire Detected ('09-10)

NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review GENERAL TROUBLESHOOTING INFORMATION .
  1. Turn the ignition switch to ON (II).
  2. Clear the DTC with the HDS.
  3. Start the engine, and let it idle without load (A/T in P or N, M/T in neutral).
  4. Monitor the OBD STATUS for DTC P0301, P0302, P0303, or P0304 in the DTCs MENU with the HDS.

    Does the screen indicate FAILED? 

    YES:  Go to step  9.

    NO:  If the HDS indicates PASSED, go to step  5. If the HDS indicates EXECUTING, keep idling until a result comes on. If the HDS indicates OUT OF CONDITION or NOT COMPLETED, wait for several minutes, and recheck.

  5. Check the CYL1 MISFIRE, CYL2 MISFIRE, CYL3 MISFIRE, and/or CYL4 MISFIRE in the DATA LIST for 10 minutes with the HDS.

    Does the CYL1 MISFIRE, CYL2 MISFIRE, CYL3 MISFIRE, and/or CYL4 MISFIRE show misfire counts? 

    YES:  Go to step  9.

    NO:  Go to step  6.

  6. Test-drive the vehicle for several minutes in the range of these recorded freeze data parameters:
    • ENGINE SPEED
    • VSS
    • REL TP SENSOR
    • CLV (calculated load value)
    • APP SENSOR
    • ECT SENSOR 1
  7. Monitor the OBD STATUS for DTC P0301, P0302, P0303, or P0304 in the DTCs MENU with the HDS.

    Does the HDS indicate FAILED? 

    YES:  Go to step  9.

    NO:  If the HDS indicates PASSED, go to step  8. If the HDS indicates EXECUTING, keep driving until a result comes on. If the HDS indicates OUT OF CONDITION or NOT COMPLETED, go to step  6 and recheck.

  8. Check the CYL1 MISFIRE, CYL2 MISFIRE, CYL3 MISFIRE, and/or CYL4 MISFIRE in the DATA LIST for 10 minutes with the HDS.

    Does the CYL1 MISFIRE, CYL2 MISFIRE, CYL3 MISFIRE, and/or CYL4 MISFIRE show misfire counts? 

    YES:  Go to step  9.

    NO:  Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals in the fuel system circuit.

  9. Turn the ignition switch to LOCK (0).
  10. Exchange the ignition coil from the problem cylinder with one from another cylinder.
  11. Test-drive the vehicle for several minutes in the range of these recorded freeze data parameters:
    • ENGINE SPEED
    • VSS
    • REL TP SENSOR
    • CLV (calculated load value)
    • APP SENSOR
    • ECT SENSOR 1
  12. Check the CYL1 MISFIRE, CYL2 MISFIRE, CYL3 MISFIRE, and/or CYL4 MISFIRE in the DATA LIST for 10 minutes with the HDS.

    Does the CYL1 MISFIRE, CYL2 MISFIRE, CYL3 MISFIRE, and/or CYL4 MISFIRE show misfire counts? 

    YES:  Go to step  13.

    NO:  Intermittent misfire due to poor contact at the ignition coil connector (no misfire at this time). Check for poor connections or loose terminals at the ignition coil.

  13. Determine which cylinder had the misfire.

    Does the misfire occur in the cylinder where the ignition coil was exchanged? 

    YES:  Replace the faulty ignition coil (see IGNITION COIL REMOVAL/INSTALLATION ), then go to step  37.

    NO:  Go to step  14.

  14. Turn the ignition switch to LOCK (0).
  15. Exchange the spark plug from the problem cylinder with one from another cylinder.
  16. Test-drive the vehicle for several minutes in the range of these recorded freeze data parameters:
    • ENGINE SPEED
    • VSS
    • REL TP SENSOR
    • CLV (calculated load value)
    • APP SENSOR
    • ECT SENSOR 1
  17. Check the CYL1 MISFIRE, CYL2 MISFIRE, CYL3 MISFIRE, and/or CYL4 MISFIRE in the DATA LIST for 10 minutes with the HDS.

    Does the CYL1 MISFIRE, CYL2 MISFIRE, CYL3 MISFIRE, and/or CYL4 MISFIRE show misfire counts? 

    YES:  Go to step  18.

    NO:  Intermittent misfire due to spark plug fouling (no misfire at this time).

  18. Determine which cylinder had the misfire.

    Does the misfire occur in the cylinder where the spark plug was exchanged? 

    YES:  Replace the faulty spark plug, then go to step  37.

    NO:  Go to step  19.

  19. Turn the ignition switch to LOCK (0).
  20. Exchange the injector from the problem cylinder with one from the another cylinder.
  21. Start the engine, and let it idle for 2 minutes.
  22. Test-drive the vehicle for several minutes in the range of these recorded freeze data parameters:
    • ENGINE SPEED
    • VSS
    • REL TP SENSOR
    • CLV (calculated load value)
    • APP SENSOR
    • ECT SENSOR 1
  23. Check the CYL1 MISFIRE, CYL2 MISFIRE, CYL3 MISFIRE, and/or CYL4 MISFIRE in the DATA LIST for 10 minutes with the HDS.

    Does the CYL1 MISFIRE, CYL2 MISFIRE, CYL3 MISFIRE, and/or CYL4 MISFIRE show misfire counts? 

    YES:  Go to step  24.

    NO:  Intermittent misfire due to bad contact at the injector connector (no misfire at this time). Check for poor connections or loose terminals at the injector.

  24. Determine which cylinder had the misfire.

    Does the misfire occur in the cylinder where the injector was exchanged? 

    YES:  Replace the faulty injector (see INJECTOR REPLACEMENT  ), then go to step  37.

    NO:  Go to step  25.

  25. Do an engine compression and a cylinder leakdown test (see ENGINE COMPRESSION INSPECTION ).

    Did the engine pass both tests? 

    YES:  Go to step  26.

    NO:  Repair the engine, then go to step  37.

  26. Do the VTEC rocker arm test (see VTEC ROCKER ARM TEST ).

    Did the engine pass the test? 

    YES:  Go to step  27.

    NO:  Repair the VTEC rocker arm (see ROCKER ARM ASSEMBLY REMOVAL ), then go to step  37.

  27. Turn the ignition switch to LOCK (0).
  28. Disconnect the injector 2P connector from the problem cylinder (see INJECTOR REPLACEMENT  ).
  29. Turn the ignition switch to ON (II).
  30. Measure the voltage between injector 2P connector terminal No. 1 and body ground.

    Is there battery voltage? 

    YES:  Go to step  31.

    NO:  Repair open in the wire between the injector and PGM-FI main relay 1, then go to step  3737.

    Fig 1: Measuring Voltage Between Injector 2P Connector Terminal No. 1 & Body Ground
    G05952881Courtesy of AMERICAN HONDA MOTOR CO., INC.
  31. Turn the ignition switch to LOCK (0).
  32. Jump the SCS line with the HDS.
  33. Disconnect ECM/PCM connector C (49P).
  34. Check for continuity between body ground and the ECM/PCM connector terminal of the problem cylinder (see table below).
    DTC TABLE

    PROBLEM CYLINDER DTC ECM/PCM TERMINAL WIRE COLOR
    No. 1 P0301 C5 BRN
    No. 2 P0302 C6 RED
    No. 3 P0303 C7 BLU
    No. 4 P0304 C8 YEL
    Fig 2: Measuring Voltage Between Body Ground & ECM/PCM Connector Terminals
    G00509541Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES:  Repair a short in the wire between the ECM/PCM and the injector, then go to step  37.

    NO:  Go to step 35.

  35. Check for continuity between appropriate injector 2P connector terminal No. 2 and the ECM/PCM connector terminal of the problem cylinder (see table below).
    DTC TABLE

    PROBLEM CYLINDER DTC ECM/PCM TERMINAL WIRE COLOR
    No. 1 P0301 C5 BRN
    No. 2 P0302 C6 RED
    No. 3 P0303 C7 BLU
    No. 4 P0304 C8 YEL
    Fig 3: Continuity Between Injector 2P Connector Terminal No. 2 & ECM/PCM Connector Terminal
    G05952883Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES:  Go to step 36.

    NO:  Repair open in the wire between the ECM/PCM and the injector, then go to step  37.

  36. At the injector side, measure the resistance between injector 2P connector terminals No. 1 and No. 2.

    Is there 10-13 Ω? 

    YES:  Go to step  46 .

    NO:  Replace the injector (see INJECTOR REPLACEMENT  ), then go to step  37.

    Fig 4: Measuring Resistance Between Injector 2P Connector Terminals No. 1 & No. 2
    G05952884Courtesy of AMERICAN HONDA MOTOR CO., INC.
  37. Turn the ignition switch to LOCK (0).
  38. Reconnect all connectors, then install the parts in the reverse order of removal.
  39. Turn the ignition switch to ON (II).
  40. Reset the ECM/PCM with the HDS.
  41. Do ECM/PCM IDLE LEARN PROCEDURE .
  42. Do CKP PATTERN CLEAR/CKP PATTERN LEARN .
  43. Test-drive the vehicle for several minutes in the range of these recorded freeze data parameters:
    • ENGINE SPEED
    • VSS
    • REL TP SENSOR
    • CLV (calculated load value)
    • APP SENSOR
    • ECT SENSOR 1
  44. Check for Pending or Confirmed DTCs with the HDS.

    Is DTC P0301, P0302, P0303, or P0304 indicated? 

    YES:  Check for poor connections or loose terminals at the ignition coils, the injectors, and the ECM/PCM, then go to the troubleshooting for DTC P0300, P0301, P0302, P0303, or P0304 (see DTC P0300, P0301, P0302, P0303, P0304: RANDOM MISFIRE AND ANY COMBINATION OF THE FOLLOWING: NO. 1 CYLINDER MISFIRE DETECTED; NO. 2 CYLINDER MISFIRE DETECTED; NO. 3 CYLINDER MISFIRE DETECTED; NO. 4 CYLINDER MISFIRE DETECTED  ).

    NO:  Go to step 45.

  45. Monitor the OBD STATUS for DTC P0301, P0302, P0303, or P0304 in the DTCs MENU with the HDS.

    Does the screen indicate PASSED? 

    YES:  Troubleshooting is complete. If any other Pending or Confirmed DTCs were indicated in step  44, go to the indicated DTC's troubleshooting.

    NO:  If the HDS indicates FAILED, check for poor connections or loose terminals at the ignition coils, the injectors, and the ECM/PCM, then go to step  1. If the HDS indicates EXECUTING, keep driving until a result comes on. If the HDS indicates OUT OF CONDITION or NOT COMPLETED, go to step  43.

  46. Reconnect all connectors.
  47. Update the ECM/PCM if it does not have the latest software (see ECM/PCM UPDATE  ), or substitute a known-good ECM/PCM (see SUBSTITUTING THE ECM/PCM ).
  48. Test-drive the vehicle for several minutes in the range of these recorded freeze data parameters:
    • ENGINE SPEED
    • VSS
    • REL TP SENSOR
    • CLV (calculated load value)
    • APP SENSOR
    • ECT SENSOR 1
  49. Check for Pending or Confirmed DTCs with the HDS.

    Is DTC P0301, P0302, P0303, or P0304 indicated? 

    YES:  Check for poor connections or loose terminals at the ignition coils, the injectors, and the ECM/PCM. If the ECM/PCM was updated, substitute a known-good ECM/PCM (see SUBSTITUTING THE ECM/PCM ), then go to step  48. If the ECM/PCM was substituted, go to step  1.

    NO:  Go to step 50

  50. Monitor the OBD STATUS for DTC P0301, P0302, P0303, or P0304 in the DTCs MENU with the HDS.

    Does the screen indicate PASSED? 

    YES:  If the ECM/PCM was updated, troubleshooting is complete. If the ECM/PCM was substituted, replace the original ECM/PCM (see ECM/PCM REPLACEMENT  ). If any other Pending or Confirmed DTCs were indicated in step  49, go to the indicated DTC's troubleshooting.

    NO:  If the HDS indicates FAILED, check for poor connections or loose terminals at the ignition coils, the injectors, and the ECM/PCM. If the ECM/PCM was updated, substitute a known-good ECM/PCM (see SUBSTITUTING THE ECM/PCM ), then go to step  48. If the ECM/PCM was substituted, go to step  1. If the HDS indicates EXECUTING, keep driving until a result comes on. If the HDS indicates OUT OF CONDITION or NOT COMPLETED, go to step  48.

scientia non olet · About LEMON Manuals