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Fuel Pump System Test: Quest

  1. If engine cranks but does not start, check inertia fuel shut-off switch. Switch is located behind driver's kick panel and is accessible through hole in kick panel. Push button down to reset switch. If gasoline fumes are present (other than during refueling), locate and repair cause of smell before resetting switch.
  2. Turn ignition on. With fingers, pinch fuel feed hose at fuel filter. Fuel pressure pulsation should be felt for 5 seconds after ignition is turned on. If pulsation is not felt, go to next step. If pulsation is felt, system is functioning properly.
  3. Turn ignition off. Disconnect fuel pump relay. Fuel pump relay is located in relay box in front of battery (second relay from left, in front row). Turn ignition on. Measure voltage between ground and fuel pump relay harness connector terminals No. 2 and No. 3 (Black/Red wires). Battery voltage should be present. If battery voltage is not present, check fuse in main fuse box. Check for open or short in appropriate wire between fuse and fuel pump relay. Repair or replace as necessary.
  4. Turn ignition off. Disconnect fuel pump harness connector (located under vehicle). Check continuity between ground and fuel pump harness connector terminal No. 3 (Black/White wire). Also check continuity between fuel pump harness connector terminal No. 2 (Light Green/Red wire) and fuel pump relay harness connector terminal No. 5. Continuity should exist in both circuits. If continuity exists in both circuits, go to next step. If continuity does not exist in either circuit, repair open or short in appropriate wire. Also check inertia switch for correct operation.
  5. Ensure ignition is off. Disconnect PCM harness connector. PCM is located under center of instrument panel (connector is on driver's side). Check continuity between fuel pump relay harness connector terminal No. 1 (Blue/Red wire) and PCM harness connector terminal No. 8. See Figure. If continuity exists, go to next step. If continuity does not exist, repair open or short in Blue/Red wire between PCM and relay.
  6. Check fuel pump relay. See RELAYS  under RELAYS & SOLENOIDS. If relay is okay, check fuel pump. See FUEL PUMP . If fuel pump relay and fuel pump are okay, check circuit harness connectors for pushed-out, bent, damaged or corroded terminals. Repair harness or connectors as necessary.
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