('11 Model) DTC P0301: No. 1 Cylinder Misfire Detected; DTC P0302: No. 2 Cylinder Misfire Detected; DTC P0303: No. 3 Cylinder Misfire Detected; DTC P0304: No. 4 Cylinder Misfire Detected
- Turn the ignition switch to ON (II).
- Clear the DTC with the HDS.
- Start the engine, and let it idle without load (CVT in P or N, M/Tin neutral).
- 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 5. If the HDS indicates EXECUTING, keep idling until a result comes on. If the HDS indicates OUT OF CONDITION, wait for several minutes, and recheck.
- 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.
- Test-drive the vehicle for several minutes in the range of these recorded freeze data parameters:
- ENGINE SPEED
- VEHICLE SPEED
- REL TP SENSOR
- CLV (calculated load value)
- APP SENSOR
- ECT SENSOR 1
- 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, go to step 6 and recheck.
- 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.
- Turn the ignition switch to LOCK (0).
- Exchange the ignition coil from the problem cylinder with one from another cylinder.
- Test-drive the vehicle for several minutes in the range of these recorded freeze data parameters:
- ENGINE SPEED
- VEHICLE SPEED
- REL TP SENSOR
- CLV (calculated load value)
- APP SENSOR
- ECT SENSOR 1
- 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.
- 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 AND SPARK PLUG REMOVAL/INSTALLATION ), then go to step 37.
NO -Go to step 14.
- Turn the ignition switch to LOCK (0).
- Exchange the spark plug from the problem cylinder with one from another cylinder.
- Test-drive the vehicle for several minutes in the range of these recorded freeze data parameters:
- ENGINE SPEED
- VEHICLE SPEED
- REL TP SENSOR
- CLV (calculated load value)
- APP SENSOR
- ECT SENSOR 1
- 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).
- 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.
- Turn the ignition switch to LOCK (0).
- Exchange the injector from the problem cylinder with one from the another cylinder.
- Start the engine, and let it idle for 2 minutes.
- Test-drive the vehicle for several minutes in the range of these recorded freeze data parameters:
- ENGINE SPEED
- VEHICLE SPEED
- REL TP SENSOR
- CLV (calculated load value)
- APP SENSOR
- ECT SENSOR 1
- 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.
- 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.
- 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.
- 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 AND SHAFT DISASSEMBLY/REASSEMBLY ), then go to step 37.
- Turn the ignition switch to LOCK (0).
- Disconnect the injector 2P connector from the problem cylinder (see INJECTOR REPLACEMENT ).
- Turn the ignition switch to ON (II).
- Measure the voltage between injector 2P connector terminal No. 2 and body ground.
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there battery voltage?
YES - Go to 31
NO - Repair open in the wire between the injector and PGM- FI main relay 1, then go to 37
- Turn the ignition switch to lock (0).
- Jump the SCS line with the HDH.
- Disconnect ECM/PCM connector C (44P).
- Check for continuity between body ground and the ECM/PCM connector terminal of the problem cylinder (see table).DTC CHART
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 Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES -Repair short in the wire between the ECM/PCM and the injector, then go to step 38.
NO -Go to step 35.
- Check for continuity between appropriate injector 2P connector terminal No. 1 and the ECM/PCM connector terminal of the problem cylinder (see table).DTC CHART
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: Checking Continuity Between Injector 2P Connector Terminal No. 1 And ECM/PCM Connector Terminal Of CylinderCourtesy 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 38.
- At the injector side, measure the resistance between injector 2P connector terminals No. 1 and No. 2.
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there 10-13Ω?
YES -Go to step 46.
NO -Replace the injector (see INJECTOR REPLACEMENT ), then go to step 38.
- Turn the ignition switch to LOCK (0).
- Reconnect all connectors, then install the parts in the reverse order of removal.
- Turn the ignition switch to ON (II).
- Reset the ECM/PCM with the HDS.
- Do the ECM/PCM idle learn procedure (see ECM/PCM IDLE LEARN PROCEDURE ).
- Do the CKP pattern clear/CKP pattern learn procedure (see CKP PATTERN CLEAR/CKP PATTERN LEARN ).
- Test-drive the vehicle for several minutes in the range of these recorded freeze data parameters:
- ENGINE SPEED
- VEHICLE SPEED
- REL TP SENSOR
- CLV (calculated load value)
- APP SENSOR
- ECT SENSOR 1
- 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: RANDOM MISFIRE AND ANY COMBINATION OF THE FOLLOWING:; DTC P0301: NO. 1 CYLINDER MISFIRE DETECTED; DTC P0302: NO. 2 CYLINDER MISFIRE DETECTED; DTC P0303: NO. 3 CYLINDER MISFIRE DETECTED; DTC P0304: NO. 4 CYLINDER MISFIRE DETECTED ).
NO -Go to step 45.
- Monitor the OBD STATUS for DTC P0301, P0302, P0303, or P0304 in the DTCs MENU with the HDS.
Does the HDS 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, go to step 43.
- Reconnect all connectors.
- 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 ).
- Test-drive the vehicle for several minutes in the range of these recorded freeze data parameters:
- ENGINE SPEED
- VEHICLE SPEED
- REL TP SENSOR
- CLV (calculated load value)
- APP SENSOR
- ECT SENSOR 1
- 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.
- Monitor the OBD STATUS for DTC P0301, P0302, P0303, or P0304 in the DTCs MENU with the HDS.
Does the HDS 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, go to step 48.