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Variable Valve Timing Control System Operation Inspection

Variable Valve Timing Control System Operation Inspection

If simulation function of WDS or equivalent is used:

1. Warm up the engine to normal operating temperature.
2. Connect the WDS or equivalent to DLC-2.
3. Start the engine and run it at idle.
4. Select VT DUTY1 PID.
5. Increase the oil control valve (OCV) duty value 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 the next step.

6. Remove the oil control valve (OCV) with connector is connected.
7. Turn the ignition switch to the ON position.
8. Select VT DUTY1 PID.
9. Increase the oil control valve (OCV) duty value and verify that the spool valve operates in the advance direction.
- If as specified, inspect the following hydraulic passage for clogging and/or leakage.
- Oil pressure switch-oil control valve (OCV)
- Oil control valve (OCV)-camshaft
- Camshaft internal passage
- If not as specified, inspect the following:
- Oil control valve (OCV) operation
- Harness and connectors for open or short (Oil control valve (OCV)-PCM terminal 2E)

10. If they are okay, replace the intake camshaft pulley (with a built-in variable valve timing actuator).

If simulation function of WDS or equivalent is not used:

1. Start the engine and run it at idle.
- If idling cannot be continued, go to Step 2.
- If idling can be continued, go to Step 7.
2. Remove the oil control valve (OCV) and verify that the spool valve is at maximum retard position.
3. Connect the oil control valve (OCV).
4. Turn the ignition switch to the ON position.
5. Verify that the spool valve is at maximum retard position.
- If the spool valve is stuck in the advance direction, inspect for the following:
- Short circuit in wiring harnesses or connectors between the oil control valve (OCV) and the PCM.

6. Inspect the variable valve timing actuator.
7. Disconnect oil control valve (OCV) connector.
8. Warm up the engine and idle it.
9. Apply battery voltage to the oil control valve (OCV) and verify that the engine idles roughly or stalls.
- If the engine idles roughly or stalls, inspect the timing belt component (valve timing deviation).
- If the engine does not idle roughly or stalls, go to the next step.

10. Remove the oil control valve (OCV) and perform spool valve operation inspection.
- If not as specified, inspect the following:
- Oil control valve (OCV)
- Harnesses and connectors between oil control valve (OCV) and PCM open or short.
- If as specified, inspect the following hydraulic passages for clogging or leakage or both:
- Oil pressure switch-oil control valve (OCV)
- Oil control valve (OCV)-camshaft
- Camshaft internal passage

11. If they are normal, replace the camshaft pulley (with built-in variable valve timing actuator).

Evaporative Emission (EVAP) System Leak Inspection
- To verify that the problem has been fixed properly after repairs, the run drive cycle or EVAP system leak inspection must be performed.

EVAP system leak inspection using WDS or equivalent

NOTE:
EVAP system test outline
- The EVAP system test, which can substituted for the run drive cycle as an EVAP control system repair confirmation method, can be done while operating the WDS in the KOEO (Key On Engine Off) condition instead of actually driving the vehicle.

EVAP system test description

- The EVAP system test finds gas leaks in the system using the PCM to monitor changes in the air pump load current of the EVAP system leak detection pump. This test starts after sending an on-demand test signal from the WDS to the PCM. The PCM controls the air pump and change-over-valve operation and also stores the load current of the air pump as follows:
i. The PCM commands turn the air pump on and retrieve the air pump load current value (LDP MON PID) as a reference current (LDP_REF PID).
ii. After retrieving a reference current value, the PCM commands the change-over-valve to open, then captures the air pump load current value (LDP MON PID) as idle current (LDP IDL PID). The EVAP system will be pressurized from this phase.







iii. The PCM continues to monitor the air pump load current value (LDPJVION PID) until the end of the test.

- You can confirm whether any evaporative gas leak occurred or not by reading the test results.

EVAP system malfunction Judgment

DTC P0442-P2407:




- The PCM calculates the stored air pump load current value and send the results to the WDS as DTCs:

Evaporative system test procedure

1. Select the EVAP system test from the Tool box on the WDS display and follow the instructions.
2. Verify that all of the following PIDs are within the specifications at the pre-test confirmation screen.






NOTE:
- To successfully perform this procedure, all PIDs must be within the following specifications before proceeding to the next step.
- The PCM will cancel the EVAP system test if the VPWR PID value falls lower than 11.0 V during the test.

3. Start the engine
4. Drive the vehicle or let the engine idle more than 20 min.
5. Turn ignition switch off, then turn it to the ON position again (Key On Engine Off).
6. Press the tick icon to start the test.
7. Verify that no DTCs present after the completion of the test.
- If any test result is indicated with red, diagnose the problem using the following DTC troubleshooting procedure or component inspection procedure.
- If any DTCs are detected, diagnose the problem using the appropriate DTC troubleshooting procedure.
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