GMC Terrain: Fuel / Water in Fuel (Diesel)

Improper fuel tank inspection or cleaning, or contaminated fuel from suppliers, can cause water to be pumped into the fuel tank along with the diesel fuel. If a WATER IN FUEL - CONTACT SERVICE message displays, the water must be drained immediately.


Diesel fuel containing water is still combustible. You or others could be burned. If the fuel needs to be drained, keep sparks, flames, and smoking materials away from the mixture.


Water in the diesel fuel can corrode internal components of the fuel system and lead to severe damage. It can also support fungus or bacteria growth, which can damage the fuel system and Fuel Operated Heater (FOH) (if equipped). Even with a diesel fuel biocide, the fuel system may still need to be cleaned. Your dealer can advise of the appropriate solution.

If the fuel tank needs to be purged to remove water, see your dealer or a qualified technician. Improper purging can damage the fuel system and block the FOH.

As an added precaution, drain the diesel fuel filter of residual water at every engine oil change. If the WATER IN FUEL - CONTACT SERVICE message comes on frequently, even after draining water from the fuel filter, see your dealer.

Water in Fuel Troubleshooting

If the WATER IN FUEL - CONTACT SERVICE message comes on:

GMC Terrain. Water in Fuel (Diesel)

GMC Terrain. Water in Fuel (Diesel)

GMC Terrain. Water in Fuel (Diesel)


Driving with this message on can damage the fuel injection system and the engine. If the message comes on right after a refuel, water was pumped into the fuel tank. Turn off the engine and drain the water immediately.

Removing Water from the Fuel Filter

To drain water:

  1. Turn the engine off and apply the parking brake.
  2. Place a container under the filter drain valve, which is on the bottom of the fuel filter.

    GMC Terrain. Water in Fuel (Diesel)

    FWD Shown, AWD Similar

  3. Turn the drain plug counterclockwise using a suitable tool.
  4. With the engine off, press and hold ENGINE START/STOP without applying the brake for five seconds to place the vehicle in Service Mode. See Ignition Positions. Wait approximately five seconds, and then press ENGINE START/STOP again to turn it off. This operation will enhance water flow out of the filter. The filter is drained as soon as diesel fuel emerges from the port.
  5. Retighten the drain plug by turning it clockwise.
  6. Properly dispose of the water contaminated fuel.
  7. Start the engine and let it run for a few minutes. During the draining process, air may have entered the fuel system. If the engine stalls, the fuel system may need to be primed. See “Fuel Priming” following.

Fuel Priming

For the fuel system to work properly, air cannot be in the fuel lines. If air gets in, the engine may not start and the fuel lines will need to be primed before operating the vehicle.

If air is present, the following may have happened:

  • The vehicle ran out of fuel.
  • The fuel filter was removed.
  • The fuel lines were removed or disconnected.
  • The fuel filter water drain valve was opened while the engine was running.

To prime the fuel lines:

  1. With the engine off, press and hold ENGINE START/STOP without applying the brake for five seconds to place the vehicle in Service Mode. See Ignition Positions 0 195. Wait approximately five seconds and press ENGINE START/ STOP again to turn it off. Do this step three times or more while the engine is off.
  2. Press and hold ENGINE START/STOP while applying the brake for a maximum of 40 seconds at a time, with five seconds between attempts, until the engine starts. If the engine tries to run, but does not run smoothly, increase the rpm’s slightly by using the accelerator pedal. This will help force air through the system.
  3. Repeat Step 2 if the engine stalls and will not restart.
  4. After a few attempts, if the engine still does not start, see your dealer.

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      Vehicle Messages

      Messages displayed on the DIC indicate the status of the vehicle or some action that may be needed to correct a condition. Multiple messages may appear one after another.

      The messages that do not require immediate action can be acknowledged and cleared by pressing V. The messages that require immediate action cannot be cleared until that action is performed.

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