Peugeot 406 Diesel Particulate Filter DPF (1995-2004)

The Diesel Particulate Filter (DPF) on the Peugeot 406 Diesel models, primarily the 2.0 HDI with RHZ/DW10ATED and similar engines, is an exhaust system component designed to trap 99.9% of harmful diesel particulates. It uses a ceramic or silicon carbide filter and a special additive to facilitate soot combustion, complying with Euro 3 and Euro 4 emission standards.

Exhaust gases pass through the porous filter where soot particles are captured. The DPF regenerates soot deposits mainly in three ways:

• Passive regeneration: Occurs during long, high-temperature drives (above 450°C) where soot burns off naturally thanks to the catalytic converter and additive.
• Active regeneration: Engine management injects extra fuel to raise exhaust temperature and burn soot; this happens approximately every 350-800 km and is limited to engine speeds below 2200 rpm.
• Forced regeneration: Performed at a garage using a diagnostic tool to run the engine at idle and high rpm with post-injection to clear the DPF.

Pressure sensors monitor soot loading to detect clogging. The DPF is situated after the catalytic converter in the exhaust line.

Common signs of a defective DPF include:

• Increased fuel consumption
• Reduced engine power or performance
• Illumination of the Check Engine warning light due to overpressure or filter overload

If you experience these symptoms, it is advisable to have the system checked by a professional garage with diagnostic equipment.

Maintenance options include:

• Cleaning without removal: Regular drives of 25-30 minutes at speeds of 60-80 km/h help passive regeneration. Products like special DPF cleaners and diagnostics tools such as VCDS can also aid cleaning.
• Replacement intervals: Preventive replacement is recommended around every 120,000 km, although actual DPF lifespan varies from 130,000 to 190,000 km depending on usage and clogging.
• Replacement procedure: Involves removing the ceramic filter, draining and resetting the additive reservoir, and erasing fault codes via diagnostics.

It is essential to use original or approved replacement parts to ensure long-term reliability and compliance with emission standards.

While occasional driving with a partially clogged DPF might be unavoidable, it is not recommended to continue driving for long periods with a faulty DPF as it causes loss of power, increased fuel consumption, and potential engine damage. Additionally, such conditions may trigger emissions-related warnings and can cause a vehicle to fail emissions testing.

It is important to address DPF faults promptly with proper service or replacement to avoid fines and to ensure your vehicle remains compliant with emission regulations.

Pressure washing a DPF is generally not recommended unless done by specialized professionals with appropriate equipment and methods, as incorrect cleaning can damage the filter's internal ceramic structure. If pressure washing is performed, it should be done carefully and typically in the opposite direction of exhaust flow to avoid damaging the filter.

For most users, allowing proper regeneration through driving or using approved chemical cleaners is the preferred method.

The Peugeot 406 2.0 HDI Diesel DPF system is designed for the following specs:

• Engine power: 109 HP (80 kW)
• Applicable engines: RHZ (DW10ATED), RHS (DW10ATED), 4HX (DW12TED4/FAP)
• Emission standards: Primarily Euro 4 compliant, also compatible with Euro 3
• DPF materials: Typically made of cordierite ceramic or silicon carbide, installed downstream of the catalytic converter
• DPF regeneration control integrated into engine control unit managing fuel injection and air temperature

Additional resources include detailed video explanations on DPF operation, maintenance tips, and aftermarket parts suppliers specializing in Peugeot 406 DPFs. For precise diagnostics and quality service, it is recommended to consult authorized Peugeot garages equipped with official diagnostic tools like DiagBox.

When purchasing DPF parts, choose original or approved parts certified to meet or exceed European standards, ensuring durability, performance, and compliance.

Always ensure regular maintenance, proper driving conditions for regeneration, and timely replacement to keep your Peugeot 406 Diesel running efficiently with minimal emissions impact.