What should the oil pressure be at idle (800 rpm) ? I just bought an 88-SE, 91K and the engine is in great shape. When I bring the car to a stop, the pressure gauge will settle at 25-30 psi for a little while and then slowly drop a little further. when i rev it back up the pressure will climb close to 60 psi. Looks like a malfunctioning sender to me but not sure.

 

Sending unit. For peace of mind buy a mechanical oil pressure gauge and patch it in to find out what the real pressure is. Then you can take it off.