The CVVT (Continuously Variable Valve Timing) system is installed to the chain sprocket of the intake camshaft. This system controls the intake camshaft to provide the optimal valve timing for every driving condition. The ECM controls the Oil Control Valve(OCV), based on the signals output from mass air flow, throttle position and engine coolant temperature. The CVVT controller regulates the intake camshaft angle using oil pressure through the OCV. As result, the relative position between the camshaft and the crankshaft becomes optimal, and the engine torque improves, fuel economy improves, exhaust emissions decrease under overall driving conditions.
PCM monitors timing misalignment while no active faults is present and fully warmed up engine oil at idle.
If the timing is misaligned PCM determines that a fault exists and a DTC is stored.
Item | Detecting Condition | Possible cause |
DTC Strategy | ● Determines if CAM target is aligned correctly to crank | ● loosened CKPS ● Timing Misalignment |
Enable Conditions | ● No active faults ● Fully warmed up at idle | |
Threshold value | Case 1 | ● 1 teeth misalignment at 80 ℃(176 ℉) < Oil Temperature < 90 ℃(194℉) |
Case 2 | ● 2 tooth misalignment at Lower than 80 ℃(176 ℉) or Higher than 90 ℃(194℉) | |
Diagnosis Time | ● Continuous (Within 1min.) | |
MIL On Condition | ● 2 driving Cycles |
Engine Oil Temperature | Misalignment |
80 ℃(176 ℉) < Engine Oil Temperature < 90 ℃(194℉) | 1 teeth |
Less than 80 ℃(176 ℉) or Higher than 90 ℃(194℉) | 2 tooth |