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Home >> GMC >> 1994 >> Forward Control 4.3 Z, Automatic >> Repair and Diagnosis >> External Pages >> Different car >> Section 15 (Engine Controls - Remove/Install/Overhaul) >> Fuel System (Diesel) >> Water-In-Fuel Warning Light
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Water-In-Fuel Warning Light

WARNING: This page does not describe the selected car, but rather 10 other vehicles, including the 1994 GMC Yukon, 1994 GMC Suburban, 1994 GMC Pickup, 1994 GMC Cab & Chassis, and 1994 GMC C3500 HD. However, it is still accessible from the selected car via links, so may be relevant.
  1. Fuel filter should be drained every 5000 miles, or when WATER-IN-FUEL warning light comes on. Diesel fuel can damage asphalt and painted surfaces. Always place a drain pan under drain hose to collect fuel.
  2. Stop vehicle and turn engine off. Apply parking brake. Remove fuel tank cap. Open water drain valve 2-3 turns. Start and allow engine to idle for 2 minutes or until clear fuel is observed. Turn engine off and close water drain valve.
  3. Install fuel tank cap. If WATER-IN-FUEL warning light comes on after driving a short distance, or if engine runs rough or stalls, a large amount of water may be present in fuel tank. Purge fuel system. See PURGING FUEL SYSTEM  under FUEL SYSTEM (DIESEL).