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Ignition Timing Inspection

  1. Remove the engine compartment covers (see ENGINE COMPARTMENT COVER REPLACEMENT ).
  2. Connect the HDS to the DLC (see HOW TO USE THE HDS (HONDA DIAGNOSTIC SYSTEM) ).
  3. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.
  4. Make sure the HDS communicates with the vehicle and the ECM/PCM. If it does not communicate, troubleshoot the DLC circuit (see DLC CIRCUIT TROUBLESHOOTING ).
  5. Check for DTCs (see GENERAL TROUBLESHOOTING INFORMATION ). If a DTC is present, diagnose and repair the cause before continuing with this test.
  6. Start the engine. Hold the engine speed at 3, 000 RPM with no load in neutral (M/T model) or P or N (A/T model) until the radiator fan comes on, then let it idle.
  7. Check the idle speed (see IDLE SPEED INSPECTION ).
  8. Jump the SCS line with the HDS.
  9. Connect the timing light to the No. 1 ignition coil harness.
    Fig 1: Identifying Timing Light At No. 1 Ignition Coil Harness
    G08068576Courtesy of AMERICAN HONDA MOTOR CO., INC.
  10. Aim the light toward the pointer (A) on the timing belt lower cover. Check the ignition timing under a no load condition (headlights, blower fan, rear window defogger, and air conditioner are turned off).
    NOTE: The other pointer (B) is not used.

    Ignition Timing 

    M/T model: 10 ± 2 ° BTDC (RED mark (C)) at idle in neutral 

    A/T model: 10 ±2 ° BTDC (RED mark (C)) at idle in P or N 

    Fig 2: Identifying Pointers And Red Marks For Ignition Timing
    G08068577Courtesy of AMERICAN HONDA MOTOR CO., INC.
  11. If the ignition timing differs from the specification, check the cam timing. If the cam timing is OK, 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 ), then recheck. If the system works properly, and the ECM/PCM was substituted, replace the original ECM/PCM (see ECM/PCM REPLACEMENT ).
  12. Disconnect the HDS and the timing light.
  13. Install the engine compartment covers (see ENGINE COMPARTMENT COVER REPLACEMENT ).