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Home >> GMC >> 1993 >> Forward Control 7.4 N >> Repair and Diagnosis >> External Pages >> Different car >> Section 120 (Engine Controls - Basic Testing - 6.5L Diesel) >> Basic Fuel System Checks >> Fuel Pump Flow Test
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Fuel Pump Flow Test

WARNING: This page does not describe the selected car, but rather 20 other vehicles, including the 1994 GMC Yukon, 1994 GMC Vandura Special, 1994 GMC Vandura, 1994 GMC Suburban, and 1994 GMC Rally Camper Special. However, it is still accessible from the selected car via links, so may be relevant.
  1. Disconnect fuel line at fuel filter inlet. Disconnect fuel injection pump electric shut-off solenoid wire (Pink).
  2. Crank engine 15 seconds. If fuel pump does not supply approximately 1/2 pint of fuel in 15 seconds, go to FUEL SYSTEM PRESSURE TEST .