Fuel Pressure Regulator
Fuel pressure regulator is located in fuel rail at rear of the engine. It consists of a fuel inlet, outlet, vacuum port and internal diaphragm. Regulated fuel pressure varies depending on intake manifold vacuum acting on fuel pressure regulator diaphragm. As vacuum increases, regulated fuel pressure is reduced. Fuel pump pressure should be 35-38 psi (2.4-2.6 kg/cm2 ). By maintaining constant fuel pressure, quantity of fuel injected for a given duration of injector on-time, remains constant.
Excess fuel is returned to fuel tank. Fuel pressure regulator failure will cause a rich mixture at idle and a normal mixture at full load, or engine flooding, or a leak mixture. Fuel pressure regulator failure will not illuminate MIL, but other faults caused by failure may illuminate MIL.
Friday, October 30th, 2009 AT 7:27 PM