Ignition Timing Inspection

Connect the Honda Diagnostic System (HDS) to the data link connector (DLC) (see step 2 on GENERAL TROUBLESHOOTING INFORMATION ).
Turn the ignition switch to ON (II).
Make sure the HDS communicates with the vehicle and the engine control module (ECM)/powertrain control module (PCM). If it doesn't communicate, troubleshoot the DLC circuit (see DLC CIRCUIT TROUBLESHOOTING ).
Check for DTCs (see GENERAL TROUBLESHOOTING INFORMATION ). 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 with no load (in P or N) (A/T model) or neutral (M/T model) 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 Timing Light
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Aim the light toward the pointer (A) on the cam chain case 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).
Ignition Timing

M/T model: 0°±2° BTDC (WHITE mark) at idle in neutral

A/T model: 0°±2° BTDC (WHITE mark) at idle in N or P

Fig 2: Identifying Timing Mark On Crankshaft Pulley
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/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 ).
Disconnect the HDS and the timing light.