Variable Valve Timing Control System Operation Inspection

When Idling cannot be continued
1. Remove the OCV (oil control valve) and verify that the spool valve is at maximum retard position.
2. If the spool valve is stuck in advance direction, replace the OCV (oil control valve).
3. Connect the OCV (oil control valve).
4. Turn the ignition switch on.
5. Verify that the spool valve is at maximum retard position.
6. If the spool valve is stuck in advance direction, inspect for the following.
- Short circuit in harnesses or connectors between the OCV (oil control valve) and the PCM.

7. Inspect the VTCS actuator.

When idling can be continued
- Not using the SSTs (NGS tester)
1. Disconnect the OCV (oil control valve).
2. Start the engine and let it idle.
3. Verify that rough idle occurs or the engine stalls when B+ is applied between the OCV (oil control valve) terminals.
4. If not as specified, inspect the following.
- OCV (oil control valve) operation.
- Following hydraulic passages for clogging or leakage.
- Oil pressure switch - OCV (oil control valve)
- OCV (oil control valve) - camshaft
- Camshaft internal passage

5. If they are okay, replace the intake camshaft pulley (with a built-in VTCS actuator).
6. Inspect for open or short harnesses or connectors between the OCV (oil control valve) and the PCM.
- Using the SSTs (NGS tester)

7. Warm up the engine.
8. Open the fuse box cover.




9. Connect the SSTs (NGS tester) to the DLC-2.
10. Idle the engine.
11. Select the "PID/DATA MONITOR AND RECORD" function on the NGS display.
12. Select the following PIDs.
- RPM
- VT ACT
- VT TGT

13. Shift the selector lever to neutral (MTX), or P position or N range (ATX). Depress the AP so that the engine speed is 4,500 - 5,000 rpm. Verify that VT ACT value follows VT TGT value by ±5° CA.

NOTE:
- When the PCM memory is cleared by disconnecting the battery cable,etc., the OCV (oil control valve) learning value is also cleared. In this case, when the inspection in Step 4 is performed, the rate that the VT ACT value follows the VT TGT value may be lowered.
- For ATX vehicles, when the inspection in Step 4 is performed in D range with the engine stalled (approx. 1,500 rpm), the VT TGT value becomes larger that of the no-load, racing speed. This facilitates verification of follow-up.

WARNING: Performing D range inspection for an ATX vehicle is dangerous. The vehicle can start suddenly, causing serious Injury. Be sure to apply the parking brake and block the wheels before the inspection.




14. Select the SIMULATION TEST function on the NGS display.
15. Select OCV PD.
16. Set the OCV (oil control valve) duty value to 100% and verify that the engine idles roughly or stalls.
- If as specified, inspect the timing belt component (valve timing deviation).
- If not as specified, go to Step 10.

17. Remove the OCV (oil control valve) and connect the OCV (oil control valve) connector to the OCV (oil control valve).
18. Turn the ignition switch on.




19. Select the SIMULATION TEST function on the NGS display.
20. Select OCV PID.
21. Set the OCV (oil control valve) duty value to 100% and verify that the spool valve operates in the advance direction.
22. If not as specified, inspect the following.
- OCV (oil control valve) operation.
- Harnesses and connectors between the OCV (oil control valve) and the PCM for open or short.

23. Inspect the following hydraulic passages for clogging and/or leakage.
- Oil pressure switch - OCV (oil control valve)
- OCV (oil control valve) - camshaft
- Camshaft internal passage

24. If they are okay, replace the intake camshaft pulley (with a built-in VTCS actuator).