I have a 1996 bonneville, and after driving for 10 to 15 min. the oil pressure guage drops. It only happens when it the rpms go under 1 or 1.5. If i stop at lights, or stop signs i have been forced to put it into neutral and rev the engine just so the rpm is above 1. I have no idea what the problem is, and it makes me nervous because it is this student/single mom'* only form of transportation. Does anyone have a clue?

It is normal for the pressure to drop after warm up. What pressure does the gage read? Any engine noise or alarms on the dash? Let us know.

when i say the oil pressure guage drops, i mean it goes so low that it reads no oil pressure. and the check guages light goes on.

The only way to know for sure what the oil pressure is is to use a mechanical tester. When it drops do you hear tapping coming from the engine? If not, the pressure is not that low. Change the oil pressure sending unit.