Mazda CX-9 Grand Touring 2009 Manual page 1404

5. Inspect the variable valve timing actuator.
When idling can be continued
For right bank
1. Disconnect OCV (RH) connector.
2. Warm up the engine and it at idle.
3. Apply the battery voltage to the 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 stall, go to the next step.
4. Remove the OCV (RH) and perform spool valve operation inspection. (See OIL CONTROL VALVE
(OCV) REMOVAL/INSTALLATION [MZI-3.7] .)
If not as specified, inspect the following:
OCV (RH)
Harnesses and connectors between OCV (RH) and PCM have an open or short circuit.
If as specified, inspect the following right bank hydraulic passages for clogging or leakage, or both.
Oil pressure switch - OCV
OCV - camshaft
Camshaft internal passage
5. If they are normal, replace the right bank camshaft pulley (with built-in variable valve timing actuator).
For left bank
1. Disconnect OCV (LH) connector.
2. Warm up the engine to idle.
3. Apply the battery voltage to the 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 stall, go to the next step.
4. Remove the OCV (LH) and perform spool valve operation inspection. (See OIL CONTROL VALVE
(OCV) REMOVAL/INSTALLATION [MZI-3.7] .)
If not as specified, inspect the following:
OCV (LH)
Harnesses and connectors between OCV (LH) and PCM have an open or short circuit.
If as specified, inspect the following left bank hydraulic passages for clogging or leakage or both.
Oil pressure switch - OCV
OCV - camshaft
Camshaft internal passage
5. If they are normal, replace the left bank camshaft pulley (with built-in variable valve timing actuator).
2008 Mazda CX-9 Grand Touring
2008 ENGINE Symptom Troubleshooting (MZI-3.7) - Mazda CX-9