Ignition Timing Inspection

Connect the Honda Diagnostic System (HDS) to the data link connector (DLC) (see step 2 on HOW TO USE THE HDS (HONDA DIAGNOSTIC SYSTEM) ).
Turn the ignition switch ON (II).
Make sure the HDS communicates with the vehicle and the ECM. If it doesn't, troubleshoot the DLC circuit (see DLC CIRCUIT TROUBLESHOOTING ).
Check for DTCs. If a DTC is present, diagnose and repair the cause before continuing with this test.
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 (see IDLE SPEED INSPECTION ).
Jump the SCS line with the HDS.
Connect the timing light to the service loop (white tape).

Fig 1: Identifying Ignition Timing Mark
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Aim the light toward the pointer (A) on the cam chain case. Check the ignition timing under a no load condition (headlights, blower fan, rear window defogger, and air conditioner are turned off).
Ignition Timing:

8 ° ±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 engine control module (ECM) if it does not have the latest software (see ECM UPDATE ), or substitute a known-good ECM (see SUBSTITUTING THE ECM ), then recheck. If the system work properly, and the ECM was substituted, replace the original ECM (see ECM REPLACEMENT ).
Disconnect the HDS and the timing light.