1. Turn off following electrical loads.
- Power steering
- A/C
2. Connect a timing light to the high-tension lead of No.1 cylinder.
3. Connect data link connector terminals TEN and GND with the Special Service Tool (System selector).
4. Start the engine and verify that the ignition timing retards as the engine warms up.
5. If not as specified, check the PCM terminal 30 (Engine coolant temperature sensor) voltage.
6. Disconnect the Special Service Tool.
7. Verify that the engine is completely warmed up.
8. Increase the engine speed and verify that the ignition advances accordingly.
9. If not as specified, check voltage at following terminals.
- PCM terminal 3E (Mass air flow sensor)
- PCM terminal 4AH 4AL (Crankshaft position sensor)