What does 'Oil Pressure Abnormal, Please Turn Off the Engine' mean?

[AlejandroFitz]

Oil Pressure Abnormal, Please Turn Off the Engine is a problem with the oil filter check valve. If the oil filter is ruled out, then there is a check valve underneath the oil filter that needs to be replaced. Below is an introduction to the oil pressure regulator: Definition: The oil pressure regulator is essentially a flow-type relief valve controlled by a diaphragm. The diaphragm divides the regulator into an upper spring chamber and a lower fuel chamber. The diaphragm controls the opening of the relief valve to maintain pressure balance between the upper and lower chambers. Working Principle: When the fuel chamber's oil pressure rises above the combined force of the spring pressure and vacuum gas pressure, the diaphragm arches upward, opening the regulator valve. Some fuel flows back to the tank through the return port via the ball valve, reducing the fuel pressure. When the pressure drops to the regulator's set control pressure, the ball valve closes to maintain a certain pressure in the oil circuit from the pump's one-way valve to the pressure regulator.