In all V6 models and 2005 and later VS models, Variable Valve Timing (VVT-i) is employed and intake camshaft timing is varied within the range of 50 degrees for V6 models depending on the conditions of driving, and between 44 degrees for V8 models as well. This system includes two sensors of the CMP/VVT-i, PCM, two oil control valves of the VVT-i and two controllers, namely the intake camshaft sprocket/actuator; both V6 and the V8 models are quite similar in their mechanism differences being observed in the controller designs. Back in the V6 models the parts of the controllers are the timing rotor, the housing which has the impeller type vane, lock pin as well as the timing chain sprocket for the intake camshaft; when the pressure of the oil is exerted to the vane, then it rotates leading to the variation of the valve timing. A few variants of V8 models include a housing, four vanes, and a lockpin which have the same working as that of the adjust valve time through the oil pressure. The actuator moves the camshaft clockwise in relation to the crankshaft when oil is supplied to the advance side and counter clockwise when supplied to the retard side; this is made possible through the pcm governing the supply of oil to the advance or retard side depending on the desired position of the camshaft. The camshaft timing oil control valve that PCMS controls, regulates the flow of oil to the passages accompanied by two values per every intake camshaft. For component replacement, V6 models are fitted with two CMP/VVT sensors mounted on the cylinder heads for the V6 models while 2005 and later V8 models have two WT sensors with the sides of the intake manifold of the valve covers. There is removal of the negative battery terminal and engine or throttle body, air filter housing or intake duct, and the disconnecting electrical connectors, and removal of mounting bolts of the sensors or oil control valves with reinstallation being the reverse of these procedures.