Mercedes B-Class Diesel Particulate Filter DPF

The Diesel Particulate Filter (DPF) in Mercedes B-Class diesel models, especially the W245 (e.g., B180/B200 CDI), is designed to capture fine exhaust particulates to reduce pollution. It traps soot particles in the exhaust gases, helping the vehicle meet emission standards.

The DPF self-cleans through a process called regeneration, where the vehicle raises exhaust temperatures above 600°C to burn off collected soot, mainly during high-speed driving like highway use.

Signs of DPF blockage include:

• Reduced engine power and responsiveness
• Increased fuel consumption
• "Service" warning light on the dashboard
• Error codes indicating excessive filter fill rates (e.g., code 246 309 for blockage over 200%)
• Messages warning of filter clogging risks

These symptoms generally occur due to driving mainly at low speeds or short urban trips, which can prevent proper DPF regeneration.

To properly diagnose the DPF system, follow these steps:

• Check the engine operating temperature reaches around 85-90°C for regeneration to initiate
• Verify sensor connectors (differential pressure sensor and back pressure sensor) are securely plugged and clean, using WD40 if necessary
• Inspect hoses for leaks, cracks, or disconnections
• Test the differential pressure sensor, which often fails and may require replacement using OE compatible parts
• Use an OBD reader to check error codes related to DPF performance

If sensors or hoses are faulty, replacing them along with cleaning can prevent DPF damage and maintain system efficiency.

DPF regeneration is an automatic process that burns soot at high temperatures by injecting additional fuel to raise exhaust heat above 600°C. It is most effective during long highway drives.

While some drivers attempt to force regeneration via specific diagnostic tools, it is generally safer to:

• Drive at sustained high engine speeds on the motorway
• Avoid frequent short urban trips that prevent the DPF from reaching regeneration temperature

Improper or incomplete regenerations can cause soot build-up and trigger DPF malfunctions and error codes.

Proper maintenance includes:

• Regular driving at higher RPMs and on open roads to allow natural regeneration
• Professional cleaning every 50,000 to 100,000 km in mainly urban use to remove ash and soot deposits
• Checking and replacing faulty sensors and hoses promptly to avoid damage

Professional cleaning involves removing the DPF and performing flow and pressure tests before a safe chemical wash. Avoid using high-temperature ovens that can damage the filter structure.

Replacement is recommended when:

• DPF is clogged beyond cleaning or regeneration capability
• Sensors are irreparably damaged
• Loss of engine power, high fuel consumption, and persistent error codes continue after maintenance

Krosfou offers brand-new, high-quality DPFs for Mercedes B-Class models, manufactured in stainless steel with advanced monolith technology. They come with a 3-year warranty (up to 100,000 km) and are designed specifically for W245 diesel engines (B180/B200 CDI).

Parts include pressure sensors, gaskets, hoses kits, and are compliant with Euro 4 standards. Replacing a DPF restores engine performance, fuel efficiency, and emission control.

Yes, alternatives include:

• Professional regeneration which cleans the DPF to near-new condition by measuring air and pressure flow and performing chemical washes (~200-400€ cost)
• Using additives or chemical treatments to boost combustion temperature and help soot burn off during short trips
• DIY cleaning following expert guides, though this carries risks if not done properly

Professional cleaning and regular maintenance can significantly extend the DPF’s life and reduce costly replacements.

The DPF is generally reliable with a lifespan of 150,000 to 250,000 km if properly maintained. Common issues include soot clogging from urban use and sensor or hose problems causing fault codes.

• Many owners report restored performance with quality replacement parts and professional cleaning
• Regular high-speed driving promotes DPF regeneration and longevity
• Checking and replacing pressure sensors simultaneously with hoses is recommended to avoid repeated problems

For accurate diagnostics and maintenance, always consult official Mercedes service or a certified garage. Proper DPF care helps save fuel, reduce emissions, and protect your vehicle’s engine.