Ignition Timing Inspection

Connect the Honda Diagnostic System (HDS) to the data link connector (DLC), 2000-2005 models (see GENERAL TROUBLESHOOTING INFORMATION ), 2006-2009 model (see GENERAL TROUBLESHOOTING INFORMATION ), and check for DTCs. If a DTC is present, diagnose and repair the cause before inspecting the ignition timing.
Turn the ignition switch ON (II).
2006-2009 model: Make sure the HDS communicates with the vehicle and the engine control module (ECM). If it doesn't, troubleshoot the DLC circuit (see DLC CIRCUIT TROUBLESHOOTING ).
Start the engine. Hold the engine speed at 3,000 RPM without load (in neutral) until the radiator fan comes on, then let it idle.
Check the idle speed:
- 2000-2005 models (see IDLE SPEED INSPECTION ).
- 2006-2009 model (see IDLE SPEED INSPECTION ).
Jump the SCS line with the HDS.
Free the service loop (A) from the engine wire harness, then connect the timing light to the service loop.

Fig 1: Removing Service Loop From Engine Wire Harness
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Aim the light toward the pointer (A). Check the ignition timing under a no load condition (headlights, blower fan, and air conditioner are turned off).
Ignition Timing:

5+/-2° BTDC (RED mark (B)) at idle in neutral

Fig 2: Checking Ignition Timing
Courtesy of AMERICAN HONDA MOTOR CO., INC.
If the ignition timing differs from the specification, check the cam timing. If the cam timing is OK, update the ECM if it does not have the latest software 2006-08 model (see UPDATING THE ECM ), or substitute a known-good ECM, 2000-2005 models (see HOW TO SUBSTITUTE THE ECM FOR TESTING PURPOSES ), 2006-2009 model (see UPDATING THE ECM ), then recheck. If the system works properly, and the ECM was substituted, replace the original ECM, 2000-2005 models (see ECM REPLACEMENT ), 2006-2009 model (see ECM REPLACEMENT ).
Turn the ignition switch OFF.
Disconnect the HDS and the timing light.
Secure the service loop to the engine wire harness with wire ties.