Pressure Regulator (Turbo)

If the fuel pressure is other than that specified, the first thing to check is the fuel pressure regulator and it`s vacuum source. Remove the manifold vacuum source line to the pressure regulator and check for any cracks, replace as needed. Also check for any gasoline in the line. Gas in the vacuum line indicates the pressure regulator has an internal leak and must be replaced. Items to check are listed below in order of probability.

1. If the fuel pressure is too high:
a. Faulty pressure regulator
b. Vacuum hose to regulator cracked or poorly fitting.
c. Clogged fuel return line.

2. If fuel pressure is too low:
a. Clogged fuel filter.
b. Fuel pump defective or low pump supply voltage.
c. Faulty pressure regulator.
d. Clogged inlet in the fuel tank.
e. Fuel system leaks.