I know Gm guages are known for probs, but hopefully someone can help me specifically isolate my problem w/ a 91 firebird 305...
When stopping, my oil pressure needle will quickly drop to zero, then return to normal operating pressure. Normal driving I also get constant slight movement of needle, but at full stop, it will dive down and come back up...
Does this look like a bad sender? how can I easily isolate this problem?
Thanks in advance for the replies

 

First thing id do is check the oil level. Sounds kinda like an engine with low oil.

To isolate the problem youd have to mechanically check the pressure with a seperate gauge. Then you will know what your actual pressure is. If it matchs with the dash you have a mechanical problem. If not you have a electrical problem.

 

Yeah, check you're oil; it could be a quart low. It also could be that the oil pump pickup fell of the pump. That happened to me once and it did exactly what you are describing.