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Home >> GMC >> 1997 >> Forward Control 6.5 F >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Basic Engine Testing - 6.5L Diesel (P Series) >> Basic Fuel System Checks >> Fuel Pump Flow Test
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Fuel Pump Flow Test

  1. Disconnect fuel line at fuel filter inlet. Disconnect fuel injection pump electric shut-off solenoid wire. See the WIRING DIAGRAMS article.
  2. Crank engine for 15 seconds. If fuel pump does not supply about1/2 pint of fuel in 15 seconds, go to FUEL SYSTEM PRESSURE TEST.