Case IH ENG418 – ENG: Water in Fuel Sensor Indicates Need to Drain

The water-in-fuel sensor has detected a significant amount of water in the fuel filter/water separator. This fault is logged by the Engine Control Unit (ENG) to alert the operator of potential fuel contamination, which could lead to poor engine performance or severe damage to the high-pressure fuel injection system.

• Farmall 65C
• Farmall 75C
• Farmall 80N
• Farmall 80V
• Farmall 85C
• Farmall 90C
• Farmall 90N
• Farmall 90V
• Farmall 95C
• Farmall 100C
• Farmall 100N
• Farmall 100V
• Farmall 105C
• Farmall 105U
• Farmall 110C
• Farmall 110N
• Farmall 110U
• Farmall 110V
• Farmall 115C
• Farmall 115U
• Farmall 120C
• Farmall 120U
• Maxxum 100
• Maxxum 110
• Maxxum 115
• Maxxum 120
• Maxxum 125
• Maxxum 130
• Maxxum 135
• Maxxum 140
• Maxxum 145
• Maxxum 150
• Puma 130
• Puma 140
• Puma 145
• Puma 150
• Puma 165
• Puma 185
• Puma 200
• Puma 220
• Puma 240
• JXU Series
• 1150K
• 1850K
• 845B
• 865B
• 885B
• 521F
• 721D
• 821E
• 8010
• Luxxum
• Optum

1. 1

   Verify that the ENG 418 fault code is active (may be accompanied by a 'CHECK' or 'STOP' lamp).

2. 2

   Visually inspect the fuel/water separator bowl for any visible signs of water, which will settle at the bottom of the bowl.

3. 3

   Consider recent fueling history; if the light appeared shortly after refueling, the fuel source may be contaminated. Stop the machine as soon as it is safe to do so to prevent damage.

4. 4

   Visually inspect the water-in-fuel sensor's wiring harness and electrical connector at the bottom of the separator for signs of corrosion, damage, or loose connections.

1. 1

   Drain the fuel/water separator

   Park the machine on a level surface and turn off the engine. Place a container under the separator's drain valve (petcock) and loosen it. Allow the fluid to drain until only clean diesel fuel is flowing, then securely tighten the valve.

2. 2

   Prime the fuel system

   Turn the ignition to the 'on' position without starting the engine to run the fuel pump and purge air from the lines. Cycle the key a few times, then start the engine and let it idle for at least one minute to verify the fault code clears.

3. 3

   Clean the filter housing

   If the warning light remains on after draining, remove the fuel filter and sensor. Thoroughly clean the housing to remove any microorganisms or algae sludge that may be shorting out the sensor's probes.

4. 4

   Replace the water-in-fuel sensor

   If the warning light persists with no water present and the housing is clean, the sensor itself is likely malfunctioning and must be replaced.

5. 5

   Inspect and repair wiring

   If the fault persists, inspect the wiring harness between the sensor and the ECU for shorts or open circuits, and test for continuity with a multimeter. Disconnect the sensor plug, clean it with electrical contact cleaner, and apply dielectric grease to prevent water intrusion.