Case IH 3451 – EDC (Electronic Diesel Control) / Engine Control Unit (ECU): The fuel main filter cartridge is worn and should be replaced, but is not yet in a critical state.

The fuel filter restriction sensor has detected an abnormal pressure drop across the main fuel filter, meaning the filter media is becoming clogged with debris, contaminants, or gelled fuel.

• Tractors and combines utilizing FPT 3.4L, 4.5L, and 6.7L engines
• 580N
• 580 Super N
• 590 Super N
• TR270
• TR320
• Wheel Loaders
• B95C
• B110C
• W80C

1. 1

   Verify the Code: Use an Electronic Service Tool (EST) or the machine's diagnostic display to confirm 3451 is the only active fuel-related code.

2. 2

   Inspect Fuel Quality: Drain a small amount of fuel from the water separator to check for heavy water contamination, algae, or gelling (especially in cold weather), which can prematurely clog a filter.

3. 3

   Check the Restriction Sensor/Switch: Inspect the wiring harness and connector at the fuel filter housing. If the wiring is damaged or shorted, it can falsely trigger the code.

4. 4

   Check the Pre-Filter: Ensure the primary fuel filter/water separator isn't also clogged (which would trigger code 3455).

1. 1

   Preparation

   Park the machine on a level surface, turn off the engine, and remove the key. Allow the engine to cool.

2. 2

   Relieve Pressure

   Clean the area around the main fuel filter housing to prevent dirt from entering the fuel system.

3. 3

   Drain the Filter

   If the filter housing has a drain petcock at the bottom, open it to drain the fuel into an approved container.

4. 4

   Remove the Filter

   Using a filter wrench, unscrew the spin-on fuel filter cartridge (or open the housing if it is a drop-in paper cartridge type). Disconnect the water-in-fuel (WIF) sensor wiring if it is attached to the bottom of the filter.

5. 5

   Clean and Inspect

   Wipe the filter mounting base with a clean, lint-free rag. Ensure the old O-ring was removed with the old filter.

6. 6

   Install the New Filter

   Transfer the WIF sensor to the new filter (if applicable). Lubricate the new filter's O-ring with clean diesel fuel. Thread the new filter onto the base by hand until the gasket makes contact, then tighten an additional 3/4 to 1 full turn (or according to the filter manufacturer's printed instructions).

7. 7

   Prime the Fuel System

   Turn the ignition key to the "ON" position for 30-60 seconds to allow the electric fuel lift pump to prime the system and bleed air. You may need to cycle the key a few times. (If the machine has a manual primer pump, pump it until resistance is felt).

8. 8

   Test

   Start the engine and inspect the filter base for leaks.

9. 9

   Clear Codes

   The fault code may self-clear after the ECU detects normal fuel pressure across the filter. If it remains stored, clear it using the CNH Electronic Service Tool.