New Holland ENG 428 – Engine Controller (ECM / Engine ECU): Water in Fuel Sensor voltage is too high.

The engine control system is receiving a voltage signal from the Water in Fuel (WIF) sensor that exceeds the normal operating range, typically indicating an open circuit, a disconnected sensor, a broken wire, or a short to a power source in the sensor's wiring harness.

• T4
• T5
• T6
• T7
• T7.270
• T8
• T8000 series
• T9
• T9000 series
• TM
• TS series
• CR9090
• CX8080
• CX8090
• Grape Harvesters 10.90X
• Grape Harvesters 11.90X
• Magnum
• Steiger
• MX/TG series

1. 1

   Visual Inspection: Locate the WIF sensor at the bottom of the primary fuel filter/water separator. Ensure the electrical connector is fully plugged in and the locking tab is secure.

2. 2

   Wiring Harness Check: Inspect the wiring harness between the WIF sensor and the Engine ECU. Look for chafed wires, broken lines, or corrosion inside the connector pins, which would cause an open circuit.

3. 3

   Drain the Filter: Place a catch pan under the fuel filter and open the drain valve (or loosen the sensor) to drain any accumulated water or debris that might be interfering with the sensor probes.

4. 4

   Multimeter Test: Test the sensor for internal continuity. If the sensor has an internal break (infinite resistance), it has failed and must be replaced.

1. 1

   Preparation

   Turn off the machine, remove the key, and disconnect the negative battery terminal to prevent electrical shorts.

2. 2

   Locate the Sensor

   Find the fuel filter/water separator assembly on the engine block or chassis. The WIF sensor is threaded into the bottom of the filter bowl.

3. 3

   Disconnect

   Unplug the electrical harness connector from the WIF sensor.

4. 4

   Remove the Sensor

   Place a drain pan underneath the filter. Unscrew the WIF sensor from the bottom of the fuel filter. Allow the fuel/water mixture in the filter to drain completely.

5. 5

   Install the New Sensor

   Lubricate the O-ring on the new WIF sensor with a small amount of clean diesel fuel. Thread the new sensor into the bottom of the filter housing by hand to avoid cross-threading, then tighten to OEM specifications (usually hand-tight plus a quarter turn).

6. 6

   Reconnect

   Plug the electrical harness back into the new sensor until it clicks.

7. 7

   Prime the System

   Reconnect the battery. Turn the ignition key to the ON position (without starting the engine) to allow the electric lift pump to prime the fuel system and purge air. You may need to cycle the key a few times.

8. 8

   Verify

   Start the engine, check the bottom of the filter for leaks, and verify that the ENG 428 fault code has cleared from the dash/monitor.