LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> GMC >> 1993 >> Forward Control 6.2 J, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Basic Testing >> Basic Fuel System Checks (Diesel) >> Fuel Pump Flow Test
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Fuel Pump Flow Test

  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 appropriate FUEL SYSTEM PRESSURE TEST.