Do I have an oil pressure problem?

Dear Car Talk

Dear Car Talk | Sep 01, 1992

Dear Tom and Ray:

I read in my owner's manual that my oil gauge should only drop below 40 when idling. My 1988 Chevrolet Corsica drops down to 15 or 20 regularly after the car has warmed up (when it's not idling). Since my extended warranty expires in about two months, I'd like to know if this is a problem.

TOM: It may be and it may not be, Gregory. You say the gauge reads 15 or 20 pounds once the engine warms up. If the gauge is giving you an accurate reading, then you may indeed have low oil pressure. And yes, that would be very bad news for your little Corsica.

RAY: But it's possible that your only problem is an inaccurate gauge. The gauge could be getting the wrong information from the oil pressure sending unit--which is a fairly inexpensive little sensor on the side of the engine block. Or the dashboard gauge itself could be faulty.

TOM: Your dealer can test this for you very easily by doing an oil pressure test. If the oil pressure is actually OK, then he'll tell you it's either the switch or the gauge.

RAY: If the oil pressure ISN'T OK, then he'll still tell you it's the switch or the gauge and try to stall you for a couple of months.

TOM: Seriously, Gregory, you should go to your dealer and document your complaint about the low oil pressure reading. As long as you can prove that you complained about a problem during the warranty period, they are obligated to fix that problem, even if the warranty runs out before they've figured out what's wrong with the car. So get it in writing.

Get the Car Talk Newsletter

Got a question about your car?

Ask Someone Who Owns One