The fuel pressure regulator maintains a constant fuel
pressure to the fuel injectors. When the difference
between the fuel pressure and manifold pressure
exceeds 343 kPa (3,5 kgf/cm2, 50 psi), the diaphragm is
pushed upward, and the excess fuel is fed back into the
fuel tank through the fuel return pipe.
Do not smoke during the test. Keep open
flames away from your work area.
1. Attach the special tool to the service port of the fuel
filter (see page 11-133).
Pressure should be:
324 – 363 kpa (3.3-3.7 kgf/cm2, 47-53 psi)
(with the fuel pressure regulator vacuum hose dis-
connected and pinched)
2. Reconnect the vacuum hose to the fuel pressure
3. Check that the fuel pressure rises when the vacuum
hose from the fuel pressure regulator is disconnected
If the fuel pressure did not rise, replace the fuel
Fuel Supply System
Fuel Pressure Regulator (cont’d)
1. Place a shop towel under fuel pressure regulator,
then relieve fuel pressure (see page 11-132).
2. Disconnect the vacuum hose and fuel return hose.
3. Remove the two 6 mm retainer bolts.
• Replace the O-ring.
• When assembling the fuel pressure regulator,
apply clean engine oil to the O-ring and assem-
ble it into its proper position, taking care not to
damage the O-ring.
Do not smoke while working on fuel sys-
tem. Keep open flame away from your work area.