1992 Other Oldsmobile Models oil pressure sending unit error

JOHNSQUIRES

MEMBER
1992 OLDSMOBILE
6 CYL
FWD
AUTOMATIC
220,000 MILES

Every time I start my 88 Royal LS, after 20-30 seconds I get and error "oil pressure sending unit". I hit reset and the error goes away but it returns the next time I start the car.

I have replaced the sending unit 2 times. Could I be getting a false msg? What could be the problem?

John

1 Reply

RASMATAZ

MECHANIC
75,992 POSTS

Could mean a low oil pressure or the computer itself-check the oil pressure with a mechanical gauge-

Causes of low oil pressure:

Excessive main and rod bearing clearances (someone may have installed the wrong-sized bearings or standard-sized bearings on a reground crankshaft). Only 0.001-inch of extra clearance in the main bearings can reduce oil pressure up to 20 percent!

Excessive camshaft bearing clearances (a bearing may have slipped out of place when the cam was installed).

Excessive clearances inside the oil pump.

Leaks between the oil pump and engine.

Oil pump relief valve stuck open or installed backward.

A loose or mispositioned oil pickup tube (too high in oil pan).

A defective oil pressure sending unit or oil pressure gauge.

Low oil level in the oil pan.

Cracks or leaks in the oil galleries or gallery plugs.

Cracked oil pump housing (improper installation).

Oil viscosity too thin for hot weather.