Ok, got a problem with my 95 Grand AM GT (3.1 L V6) and my mechanic and I are completely stumped. When I'm driving it the oil pressure gauge is fairly low, and often while stopped (stop sign/light) the "check gauges" light goes on and the oil pressure reading goes down to the red. The check engine light and oil light do NOT go on. I don't notice any immediate difference in the idle (the engine hums, sounds great). After a while, and sometimes right at the beginning of my trip, when it does this the engine will just kill (battery light goes on, I have to restart). Again, there is no engine knocking or noise when this happens.
My mechanic checked the oil pressure using a manual gauge and says it's A-OK. He replaced the switch (I believe that's what it's called) and it made no difference. Also, just to be sure, he checked the battery and alternator and those are fine as well.
At this point, we're wondering if it's an electrical problem?!?, but I don't really want to pay a ton of money to have it checked if it's something else. Has anyone seen this or have any other ideas? Your help would be greatly appreciated.