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Home >> Ford >> 1987 >> Bronco II RWD, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Fuel Pump - Electric >> Testing >> High Pressure Fuel Pump >> MPFI Models

MPFI Models

  1. Check fuel tank(s) for adequate fuel supply. Check for fuel leaks at fittings and lines. Locate electrical connector on frame-mounted fuel pump. With ignition off, disconnect fuel pump connector from harness and connect ohmmeter across body connector.
  2. If continuity is 5 ohms or less, go to step 4. If continuity is more than 5 ohms, check for continuity between connector ground lead and ground. If no continuity exists, repair open in pump ground circuit and repeat step 2. If continuity exists, check for continuity between connector Pink/Black wire and ground.
  3. If no continuity exists, check wiring at fuel pump/sending unit. If continuity exists, check continuity across pump terminals. If continuity exists, go to step 4. If no continuity exists, replace fuel pump/sending unit. Ensure fuel pump/sending unit connections are okay.
  4. Turn ignition on. Using voltmeter, check for voltage between connector and ground. Voltage should be 12 volts for one second, then drop to zero volts. If voltage is incorrect, check wiring and repair as necessary. If voltage is correct, go to step 5.
  5. Turn ignition off. Using ohmmeter, check for continuity across pump leads. If continuity exists, perform FUEL PUMP PRESSURE TEST  . If no continuity exists, check continuity at pump terminals. If still no continuity, replace frame-mounted fuel pump.
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