oilpressure with it running

40-60lbs at idle hot.

Depends on several things. Newness of the engine, idle speed, and oil density. If your on a slow idle, 600 or below, your oil pressure will not run normal, rather low. If you have 5-20, the oil is thin, and it will read low. If you have perhaps over 75K on the engine and you have not been religious in maintenance, it may run low. Normal idle of 750 to 850 with 10 W 30 or higher it should be between 30 on the low end to 45 on the high end. 1500 RPM will or should bring it back up to normal operating range. If at 1500 it fluctuates, check the oil level, and perhaps when it was changed last. The oil should not break down, it is changed due to the amount of contaminates in the oil. That is why NPG engines can run twice as long and the oil is still visibly clean. Check your connections to the sending unit and gauge, or the sending unit itself first before tearing into the motor. Change the oil and filter and go to a higher viscosity number, like straight 30 weight and make sure the car idle is at or above 750 RPMs.