Starting problems and high fuel pressure

MICHAELR1870

MEMBER
2003 LINCOLN TOWN CAR
4.6L
V8
2WD
AUTOMATIC
130,000 MILES

My car won't start, cranks over but that's it. I have put a fuel pump driver on it. The fuel pressure is reading 80. Psi"s. I know that's too high. Would this possibility be a fuel pump regulator problem and if so is it located in the fuel tank with the pump? Or what else could it be? I'm getting fire because it will run as long as I feed gas to it. Thanks any input. Mike

Sunday, April 14th, 2019 AT 2:52 PM

1 Reply

JACOBANDNICKOLAS

MECHANIC
110,176 POSTS

Welcome to 2CarPros.

It sounds like the regulator is the problem unless you have a major vacuum leak preventing enough engine vacuum to reach the regulator or the vacuum hose is damaged or disconnected. The fuel pressure regulator (see picture 1) is attached to the fuel rail downstream of the fuel injectors. It regulates fuel pressure supplied to the fuel injectors. The regulator is a diaphragm-operated relief valve. One side of the diaphragm senses fuel pressure and the other side is connected to the intake manifold vacuum.

Picture 2 shows pressure specs.

Do me a favor. Remove one of the spark plugs and inspect it. Is it wet? If so, replace the regulator. Also, please keep in mind if that is the case, raw fuel may be entering the catalytic converter which will cause damage.

Let me know if I can help in any way.

Take care,
Joe

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