1995 Mercedes Benz S500 High Oil Pressure

Hi bigtruckbuyer. Welcome to the forum. Unlug the electrical connector to the new sending unit. If the gauge continues to read too high, suspect that wire is grounded, most commonly where the wiring harness goes over a sharp metal bracket or rubs on a rocking engine.

If the gauge goes down with the wire unplugged, and both the old and new sending units cause the same high reading, the oil pressure probably really is that high. It should be verified with a mechanical gauge. Suspect debris blocking the passage to the pressure relief valve in the oil pump. Too much pressure can cause the oil filter to rupture and it can cause excessive oil consumption from overloading the cylinder walls with oil.

Caradiodoc