Fuel Pressure
Basic diagnosis of fuel system should begin with determining fuel system pressure.
WARNING:
ALWAYS relieve fuel pressure before disconnecting any fuel injection-related component. DO NOT allow fuel to contact engine or electrical components.
- Relieve fuel system pressure. To relieve pressure, remove fuel pump fuse, start engine and allow to run until engine stalls due to lack of fuel. Crank engine an additional 2 or 3 times to verify all pressure has dissipated.
- Disconnect fuel hose on fuel filter outlet side and install fuel pressure gauge. Start engine and check fuel line connections for leakage. Check fuel pressure with engine idling. Record fuel pressure gauge reading.
- Disconnect and plug vacuum hose from pressure regulator and immediately note fuel pressure. Record fuel pressure gauge reading. See REGULATED FUEL PRESSURE table.
- Connect a hand held vacuum pump to fuel pressure regulator. Start engine and watch indication of fuel pressure gauge as vacuum is changed. Fuel pressure should decrease as vacuum increases. If result is not as specified, replace fuel pressure regulator.
REGULATED FUEL PRESSURE
| At Idle w/o Vacuum | At Idle w/Vacuum |
|---|---|
| psi (kg/cm2 ) | psi (kg/cm2 ) |
| 43 (3.0) | 34 (2.4) |