86 3.8l Looses Oil Pressure

3.8l 86 Bird Looses Oil Pressure When Engine Gets Hot. When Its Cold Its Fine. Drive It On Long Distances And The Idiot Light Comes On And Looses Pressure When I Stop At Lights Or Stop Signs. If I Keep My Foot On The Gas It Seems Ok.

the first thing you need to do is determine if it's actually losing pressure by hooking up a mechanical gage or replacing the sensor. you could try using a heavier oil. oil pressure problems are usually expensive to fix the engine bearing clearences might be to big or the pump screen clogged/ worn out pump.