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Ignition Timing Inspection

  1. Connect the HDS to the DLC (see step 2 on HOW TO USE THE HDS (HONDA DIAGNOSTIC SYSTEM) ).
  2. Turn the ignition switch to ON (II).
  3. Make sure the HDS communicates with the vehicle and the PCM. If it does not communicate, troubleshoot the DLC circuit (see DLC CIRCUIT TROUBLESHOOTING ).
  4. Check for DTCs (see GENERAL TROUBLESHOOTING INFORMATION ). If a DTC is present, diagnose and repair the cause before continuing with this test.
  5. Start the engine. Hold the engine speed at 3, 000 RPM with no load (in P or N) until the radiator fan comes on, then let it idle.
  6. Check the idle speed (see IDLE SPEED INSPECTION ).
  7. Jump the SCS line with the HDS.
  8. Connect the timing light to the No. 1 ignition coil harness.
    Fig 1: Connecting Timing Light To No. 1 Ignition Coil Harness
    G07353472Courtesy of AMERICAN HONDA MOTOR CO., INC.
  9. Aim the light toward the pointer (A) on the timing belt lower cover and the timing mark (B) on the crankshaft pulley. 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 (C) is not used.

    Ignition Timing 

    10°±2° BTDC (RED mark) at idle in P or N 

    Fig 2: Identifying Ignition Timing Points
    G07353473Courtesy of AMERICAN HONDA MOTOR CO., INC.
  10. If the ignition timing differs from the specification, check the cam timing. If the cam timing is OK, update the PCM if it does not have the latest software (see KNOCK SENSOR REPLACEMENT ), or substitute a known-good PCM (see SUBSTITUTING THE PCM ), then recheck. If the system works properly, and the PCM was substituted, replace the original PCM (see PCM REPLACEMENT ).
  11. Disconnect the HDS and the timing light.