Lubrication System

The engine lubrication system is of the force-feed type in which oil is supplied under full pressure to the crankshaft, connecting rod bearings, timing chain tensioners, camshaft bearing caps and VCT solenoids. The flow of oil to the valve tappets and valve train is controlled by a restricting orifice located in the cylinder head gasket.

The lubrication system is designed to provide optimum oil flow to critical components of the engine through its entire operating range.

The heart of the system is a continuously variable vane style oil pump, regulated with a pressure control solenoid valve.

Generically, this design operates as follows:

• Maximum oil pump displacement has been selected to provide adequate volume to insure required pressure at both hot idle and maximum speed.
• An internal relief valve protects the system from excessive pressure during high viscosity conditions. When activated, it vents bypassed oil back to the oil pan.
• In conditions other than hot idle and maximum speed, system flow and pressure are controlled with a solenoid valve, receiving commands from the powertrain control module (PCM), to deliver correct oil pressure for all operation conditions based on engine speed, load, and oil temperature.
• The solenoid valve regulates oil pump performance by controlling oil pressure in the internal control chamber of the oil pump.