Questions and Answers

Oldsmobile Aurora Oil Pressure Problem Q. Overview: Light tapping in engine, especially if the oil is low. Oil Pressure gauge reads erratically, 7 to 8 psi when hot and at a light, 50 to 65 psi when cold and first starting up.

• Manual says, "Sometimes when the engine is idling at a stop, the light may blink on and off. This is normal."
• Oil Pressure light Came on twice in last 45 days.
• When engine cold, oil pressure between 50 to 65 psi.
• As engine warms up, oil pressure drops.
• When temperature gauge reads approximately 200°, oil pressure can be as low as 7 to 8 psi at idle, but increase up to 21 to 28 psi at highway speeds.
• Car had low/no mileage for approximately six months in 2002/2003.
• Burns about a quart of oil every 3,000 miles.
• After an hour "diagnosis," Dealer said the cause of my tapping was most likely due to an internal engine problem, as my oil pressure was low, and they weren't even sure if the car would make it back home. I was approximately 400 miles away from home at the time. NEVER said anything about replacing pump, using an engine cleaner, replacing screen, etc).

QUESTIONS:

1. What should be the normal activity for oil pressure? Single digit/low double digits at idle, and 20 to 40 psi at higher speeds? Always around 40 psi on my mother-in-law's Buick.
2. Is this normal for a 1997 Aurora?
3. Do I have a problem, or in light of what the manual said, am I just super sensitive after the light came on?
4. Should I use an engine cleaner? Change the oil pump? Oil screen? Anything else?
5. What type of oil should I use in the future?
6. Anything else I should do?

• 1997 Oldsmobile Aurora
• 4.0 liter V-8
• Automatic transmission
• 92,000 miles
• ABS brakes
• P/S, A/C, Cruise control

A. The oil pressure should be at least 10 psi at idle. This would bother me even if it does say that it's normal for the light to come on at times. Sounds like it's losing pressure when it's hot. Have you tried a thicker oil?

BG makes a product, RF-7, that works pretty good. A can of this in a full crankcase of your regular oil may be all that you need. There are lots of things that could be causing the problem. Clogged oil screen, leaking oil seal at the suction pick-up tube, excessive oil clearances in the bearings. All these would require tearing into the engine to hunt for. I would try an oil additive first.