Fuel Pump Pressure Test

Relieve fuel system pressure. Refer to FUEL SYSTEM PRESSURE RELEASE . Attach Fuel Pressure Gauge Set (J-34730-1) and Adapter (J-35957-10) to outlet side of fuel filter. Install fuel pump relay. Crank engine a few times to build fuel pressure to 35-38 psi (2.5-2.7 kg/cm² ). Start engine and check for leaks. If engine will not start, fuel pump relay can be by-passed. See Figure. Also, refer to CHART A-3: ENGINE CRANKS, BUT WILL NOT RUN .
Idle fuel pressure should be 25-30 psi (1.8-2.1 kg/cm² ). Disconnect and plug vacuum hose from fuel pressure regulator. Fuel pressure should increase to 35-38 psi (2.5-2.7 kg/cm² ).
Reconnect vacuum hose. Note if fuel pressure drops slightly. Pinch off fuel supply line at flex hose momentarily and note fuel pressure. Maximum fuel pressure should be more than 65 psi (4.5 kg/cm² ).
If pressure is not within specification, check for defective fuel pump, pressure regulator or restriction in fuel system. Repair as required. Relieve fuel system pressure. Refer to FUEL SYSTEM PRESSURE RELEASE . Remove pressure gauge and adapter. Using shop towel, absorb fuel that escapes as fuel pressure is relieved. Start engine and check for fuel leaks.

NOTE: To test fuel pump relay circuit, proceed to testing in CHART A-5: FUEL PUMP RELAY CIRCUIT (IMPULSE) . Also, see Figure & Figure.