oil pressure

I have an oil pressure question. My oil pressure gauge bottoms out to 0 when I come to a stop. It's between 20 & 40 other times. I had the oil pressure checked and it was fine. Had a new gauge put in. After all that it still bottoms out to 0 when I stop. There is no problem with the way it drives. No noise coming from the engine. Is this normal for these gauges or what? By the way my Vette is an 82 Collector Edition. I'd appreciate any ideas. Thanks

Sounds like a BAD sender. It is located on left side of engine. Sticks out from the rear of the block. Has a wire hooked to it going to the guage, if it's electric. If it is direct pressure from the engine, it has a small line hooked to it, maybe plastic, or copper, located on the rear top of the engine near the distributor. Check to see if the wire is hooked up OR if the line is crimped/bent so pressure is reduced at low RPM.