I drive a 91 GTO -- i had a drop in my il pressure guage suddenly from normal to 0 while stoped at a light. there seems to be pressure in my engine--- any ideas what this could be??

The stock gauge is notoriously crappy and will real low regularly. usually the more corrosion on the electrical connections, the lower it reads. I wouldnt trust it. Just make sure you keep up on your changes and normal stuff. If it really worrys you, i would get an aftermarket gauge or check the pressure manually.

usually the cable connection come adrift, the oil pressure sender is on the drivers side at the back of the engine just under the drive shaft and above the sump, look for the round mushroom type sender, if I remmember it has a flat round connector.

^^what he said, It looks like a mushroom and it has a blade connector, I believe the connector is green as well. Might be black.