How Does CVVT Works to the Engine?

General Description:
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 signal output from mass airflow, 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 emission decrease under driving conditions.
DTC Detecting Condition
Item                 Detecting Condition                               Possible Cause =DTC               = Determines if CAM target is aligned    =loosened CKPS
Strategy          correctly to crank                              = Timing misalignment
=Enable           =No active faults                                                   
Conditions        =Fully warm up at idle                        
= Threshold       =Case 1                                           = 1teeth misalignment at 80 *C(176 *F)
value                                                                      Temperature<90*C(194*F)
= Case 2         = 2 tooth misalignment ot lower than   
                       80*C(176*F) or Higher than 90*C(194*F)
=Diagnosis       = Continuous(within 1 min.)
Time
= Mil On          = 2 driving cycles
Condition
Specification:
Engine oil Temperature:                                                                  Misalignment: 80*C(176*F)<90*C(194*F)                   1 Teeth
Info to Charging System