Lubrication Description
Engine lubrication is supplied by a variable displacement two-stage vane-type oil pump assembly (12). An oil control solenoid valve, controlled by the engine control module (ECM), mounted to the oil pump provides two stage functionality. The oil pump is mounted on the front of the engine block and driven directly by the crankshaft sprocket. The pump rotor and vanes rotate and draw oil from the oil pan sump through a pick-up screen and pipe (11). The oil is pressurized as it passes through the pump and is sent through the engine block lower oil gallery.
Pressurized oil is directed through the engine block lower oil gallery to the full flow oil filter (10) where harmful contaminants are removed. A bypass valve is incorporated into the oil filter, which permits oil flow in the event the filter becomes restricted.
Oil exits the oil filter and is then directed to the external oil cooler (8). The external oil cooler is a liquid- to- liquid (engine coolant to oil) oil cooler and consists of an oil pan mounted core and coolant lines that connect the oil cooler to the engine cooling circuit. A bypass valve (7) is incorporated into the oil cooler assembly in the event oil flow within the cooler is restricted. Then the oil moves to the upper main oil galleries and the valve lifter manifold assembly (6). Oil from the left upper oil gallery is directed to the crankshaft and camshaft bearings. Oil that has entered both the upper main oil galleries also pressurizes the valve lifter assemblies and is then pumped through the pushrods to lubricate the valve rocker arms and valve stems. Oil returning to the pan is directed by the crankshaft oil deflector. The oil pressure sensor is located at the top front of the engine.
An oil passage at camshaft bearing location 2 permits oil flow into the center of the camshaft. Oil enters the camshaft exiting at the front and into the camshaft position (CMP) actuator solenoid valve (2). The CMP valve spool position is controlled by the engine control module (ECM) and CMP magnet (1). When commanded by the ECM, the CMP magnet repositions the CMP actuator solenoid valve spool directing pressurized oil into the CMP actuator to control valve timing. Refer to Camshaft Position Actuator and Solenoid Valve Description .
With active fuel management activated, the ECM commands the 4 solenoids to open, directing oil through the engine block oil galleries to the intake and exhaust valve lifters for cylinders 1, 4, 6, and 7.