Ignition Timing Inspection

Connect the Honda Diagnostic System (HDS) to the data link connector (DLC) (see step 2 in GENERAL TROUBLESHOOTING INFORMATION ), and check for DTCs. If a DTC is present, diagnose and repair the cause before inspecting the ignition timing.
Start the engine. Hold the engine at 3,000 rpm without (in Neutral) until the radiator fan comes on, then let it idle.
Check the idle speed (see IDLE SPEED INSPECTION ).
Select "SCS" mode using the HDS.
Connect the timing light to the service loop.

Fig 1: Connecting Timing Light To Service Loop
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Aim the light toward the pointer (A) on the timing belt cover. Check the ignition timing under a no load condition (headlights, blower fan, rear window defogger, and air conditioner are turned off).
Ignition Timing: 10°+/-2° BTDC (RED mark (B)) at idle in Park or Neutral

Fig 2: Aiming Light Toward Pointer On Timing Belt Cover
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 powertrain control module (PCM) if it does not have the latest software (see PCM UPDATING AND SUBSTITUTION FOR TESTING ), or substitute a known-good PCM (see HOW TO SUBSTITUTE THE PCM ), then recheck. If the ignition system works properly, replace the original PCM (see PCM REPLACEMENT ).
Disconnect the HDS and the timing light.