Alfa Romeo 159 Diesel Particulate Filter DPF (2005-2011)

The DPF on Alfa Romeo 159 (models 939 including 159 SW and Brera) is a critical component of the diesel engine exhaust system, designed to trap carcinogenic fine particles from exhaust gases in 2.4 JTD 20V E4 and 1.9 JTDm engines. It is positioned after the turbo and often integrated with a catalytic converter to reduce emissions.

The DPF operates in two main cycles:

• Filtration: It collects soot particles on its walls, forming a layer that can reduce engine performance if not cleared.
• Regeneration: It burns off the accumulated particles at high temperatures. This process is triggered automatically when the DPF reaches about 76% capacity by sensors measuring temperature, pressure, and differential pressure.

Incomplete regeneration, such as shutting the engine off too soon, can cause residue buildup and clog the filter.

Compatible models include:

• Alfa Romeo 159 (939): 2.4 JTD 20V E4, 1.9 JTDm (8v/16v)
• Alfa 159 SW (939): 2.4 JTD 20V E4
• Alfa Brera (939): 2.4 JTD 20V E4

The DPF also fits some Opel CDTI, Fiat, Lancia, and Jeep vehicles with similar diesel engines.

Frequent issues include:

• Clogging due to frequent short drives preventing full regeneration, causing loss of performance and engine warning lights with error codes such as P2085.
• Failure of the differential pressure sensor, a common cause of DPF malfunctions, diagnosable via OBD tools that show pressure, temperature, and regeneration status.

If the pressure sensor is replaced, recalibration via the engine control unit is necessary to avoid persistent errors.

Options include:

• Original OEM DPF: Reference 51780158 from FCA/Stellantis, guaranteed quality, available from specialized Alfa Romeo suppliers.
• Aftermarket DPFs: Available for 1.9 JTDm and 2.4 JTDm, with warranties up to 3 years, supplying reliable engine function.
• DPF Pressure Sensor Replacement: Requires unscrewing sensor P2085 and recalibration using diagnostic apps such as MultiECUScan.

Preventive monitoring using apps helps track filter fill level, temperature, and pressure to force manual regeneration and avoid clogging.

Effective maintenance tips:

• Use apps to monitor DPF filling, temperature, and pressure readings in real time.
• Drive sufficient distances regularly to allow automatic regeneration cycles to complete.
• Force manual regeneration if the vehicle’s distance travelled is too short for automatic regeneration to activate fully.

These steps add service time to your filter’s life and help avoid costly replacements.

Krosfou provides:

• 3-year warranty limited to 100,000 km use under proper vehicle conditions.
• Products made from high-quality stainless steel and certified by TÜV SÜD for superior or equivalent OEM quality.
• Free returns within 30 days for unused original condition items ordered with full car details.
• Technical support manuals and professional advice available exclusively via email for installation and diagnostics.

Negligence causing clogging will void warranty; always follow manufacturer and service instructions carefully.

For further resources, consider:

• Official Alfa Romeo parts and specialist automotive websites for genuine OEM suppliers.
• Video tutorials on YouTube explaining DPF operation, sensor replacement (P2085 code), and regeneration procedures.
• Automotive forums like alfisti.net providing user experiences, tips for forced regeneration, and general advice on diesel particulate filters.
• Using diagnostic apps such as MultiECUScan for real-time DPF data monitoring and troubleshooting.

Always verify part compatibility with your vehicle’s VIN and consult qualified garages for complex repairs or replacements.

Maintain your Alfa Romeo 159’s engine and EGR system properly as part of overall DPF care to ensure your car runs efficiently and meets emission standards.