I've recently been driving an old reengined 1986 Ford Ranger, I have no idea what the engine is, the truck says electronic ignition, but this looks conventional, 2.0 l or 2.3 l. The problem is the oil pressure gauge (it's the dummy variety - I tested it by grounding the sender wire - it reads slightly about half), goes straight up to good oil pressure, but then falls to zero after a few minutes, and stays pegged at zero, although the engines runs fine, although a little hot.
Is this an indication that I'm sludging at the oil pump intake port, or is it indicative of a stripped oil pump drive gear, or is the sender just bad. I don't want to put a new sender in, I don't even want to invest in a set of good gauges, but I don't want to blow the engine, and the alternative of dropping the oil pan and desludging it almost calls for basically removing the engine.
Anyone ever seen a sender unit fail like this, or do I have a deeper problem here.
Thanks!