New Holland ENG 3815 – ENGINE: Diesel Particulate Filter (DPF): Low efficiency in DPF filter

The engine control system has detected that the DPF is no longer effectively trapping particulate matter (soot) or is failing to regenerate properly. This is typically caused by a cracked filter substrate, internal melting, or severe face plugging.

• T4.75
• T4.85
• T4.95
• T4.105
• T4.115
• T5.95
• T5.105
• T5.115
• T6
• T7
• T8
• T9.480
• L213
• L215
• L216
• L218
• L220
• L225
• L230
• L316
• L318
• L320
• C232
• C238
• B90B
• B95C
• B110C
• CX Series

1. 1

   Visual Exhaust Check: Look for black smoke exiting the exhaust pipe. If black smoke is visible, the DPF substrate is cracked or structurally compromised and must be replaced.

2. 2

   Physical Inspection: Check that the DPF is mounted properly and the external housing is not cracked or leaking exhaust gases.

3. 3

   Address Upstream Codes First: Scan for and repair all other engine problems (e.g., EGR faults, turbo boost issues, MAF sensor codes, or fuel injector failures) PRIOR to addressing the DPF. Upstream engine issues cause excess soot that leads to premature DPF failure.

4. 4

   Sensor Plausibility: Check the DPF differential pressure sensor and its hoses for blockages or leaks. Faulty pressure readings can falsely trigger efficiency codes.

5. 5

   Temperature Verification: Monitor the Exhaust Gas Temperature (EGT) sensors during a forced regeneration. The downstream temperature must reach regeneration thresholds (often over 600°C / 1100°F). If temperatures remain low, inspect the hydrocarbon injector (doser) for failure.

1. 1

   Resolve Engine Faults

   Ensure any upstream conditions preventing proper combustion or regeneration have been repaired.

2. 2

   Remove the DPF

   If the DPF has failed the efficiency monitor and is cracked or melted, it cannot be regenerated and must be removed. Disconnect the differential pressure sensor lines and EGT sensors from the DPF housing.

3. 3

   Unbolt the Assembly

   Remove the V-band clamps and exhaust flanges securing the DPF to the Diesel Oxidation Catalyst (DOC) and exhaust tailpipe.

4. 4

   Install the New DPF

   Install the replacement or remanufactured DPF. You must discard the old gaskets and seals and install new OEM gaskets, sealing rings, and O-rings to prevent exhaust leaks.

5. 5

   Reassemble

   Reconnect the V-band clamps, EGT sensors, and differential pressure lines.

6. 6

   Reset ECU Parameters

   Connect the New Holland diagnostic service tool to the machine. You MUST reset the DPF ash load / self-learning parameters in the Engine Controller. Warning: Do not reset this timer unless the DPF has been physically replaced or professionally removed and cleaned, as the ECM uses this to track soot/ash load.

7. 7

   Verify Operation

   Perform a stationary forced regeneration to verify the system reaches proper temperatures and to ensure there are no exhaust leaks.