For 1990-2009 cars

• | The oil level is low. Fill to the full mark on the oil level indicator.

• | The idle speed is slow. Refer to Engine Controls.

• | The oil pressure switch is incorrect or malfunctioning. Replace the oil pressure switch with a proper oil pressure switch.

• | The oil pressure gauge is incorrect or malfunctioning. Replace the oil pressure gauge with a proper oil pressure gauge.

• | The engine has improper oil viscosity or diluted oil.

- | Install oil of proper viscosity for expected temperature.

- | Install new oil if it is diluted with moisture or unburned fuel mixture.

• | The oil pump is worn or dirty. Clean or replace the oil pump.

• | The oil filter is plugged. Replace the oil filter.

• | The oil pickup screen is loose or plugged. Tighten or replace the oil pickup screen.

• | The oil pickup tube has a hole. Replace the oil pickup tube.

• | The connecting rod and/or crankshaft bearing have excessive clearance. Replace the connecting rod and/or crankshaft bearing(s) if necessary.

• | The oil galleries are cracked, porous, or plugged. Repair or replace the block.

• | The gallery plugs are missing or improperly installed. Install or repair the galley plugs as necessary.

• | The oil pressure regulator valve is stuck.

- | Check for the oil pressure regulator valve sticking in the oil pressure regulator bore. Repair or replace the oil pressure regulator valve as necessary.

- | Check the oil pressure regulator valve bore for scoring and burrs. Repair or replace components as necessary.

• | The camshaft is worn or poorly machined. Replace the camshaft.

• | The valve guides are worn. Repair the valve guides or replace the cylinder head as necessary.