- Connect the Honda Diagnostic System (HDS), or equivalent OBD-II compliant scan tool, to the data link connector (DLC), and check for DTC's. 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 with no load (in Park or Neutral) until the radiator fan comes on, then let it idle.
- Check the idle speed, as outlined in the Fuel System Section.
- Follow the tester's prompts to get the tester in the ''SCS'' mode (see the operator's manual).
Free the service loop from the wire harness, then connect the timing light to the service loop.
- Aim the light toward the pointer (A) on the timing belt cover. Check the ignition timing under no load condition: headlights, blower fan, rear window defogger, and air conditioner are not operating. The ignition timing should be 8-12 ° BTDC at idle in Park or Neutral.
- If the ignition timing differs from the specification, check cam timing. If cam timing is OK, substitute a known-good PCM, then recheck. If the system work properly, and the PCM was substituted, replace the original PCM.
- Disconnect the HDS and the timing light.
Secure the service loop to the wire harness with wire ties.