Alfa Romeo GT Diesel Particulate Filter DPF (2003-2010)

The Diesel Particulate Filter (DPF) on the Alfa Romeo GT, specifically models with the 1.9 JTD 150 hp engine (engine code 937A5000, manufactured between 2003/11 and 2010/03), is designed to capture up to 99 % of fine particles such as soot and ash from diesel combustion. It is located after the catalytic converter and before the exhaust silencer in the exhaust system. Only versions with 5 injection phases are fitted with a DPF, unlike earlier JTD engines with 3 phases which do not have one.

The DPF consists of a ceramic body with around 50 microscopic channels per cm² forming a filtration network. Exhaust gases pass through, but soot particles accumulate on the walls forming a filtering layer. This layer improves filtration but causes increased back pressure, which can dirty the engine and reduce power.

• Passive regeneration : At full engine load, temperatures exceeding 500-600°C naturally burn off the soot.
• Active regeneration : Triggered by the engine control unit when excessive back pressure is detected via a differential pressure sensor. The system temporarily stops the EGR valve, adds post-injection fuel, and adjusts the turbo to raise exhaust gas temperature to about 600°C. This converts soot into CO2, water vapor, and ash over 5-15 minutes typically every 500-700 km based on driving conditions.
• Additives : Lower combustion temperatures by about 100°C to allow regeneration even at low load.

Diesel DPF regenerations are more frequent than petrol due to cooler exhaust gases in diesel engines like the Alfa GT.

A clogged DPF is often signalled by a warning light on the dashboard. Common symptoms include:

• Loss of engine power
• Increased fuel consumption, especially in city driving due to repeated post-injections
• Aborted regeneration attempts in traffic jams

It is recommended to use a monitoring app compatible with Fiat, Alfa Romeo, Lancia, and Jeep vehicles to check clogging percentage (0-120 %, resetting near 21 % after regeneration), DPF temperature (~300-600°C during regeneration), differential pressure, and distance since last regeneration. Proper driving on motorways or fast roads helps passive regeneration. Avoid turning off the engine during active regeneration to prevent clogging.

Yes, manual regeneration can be initiated using diagnostic tools to optimise the DPF lifespan. This is particularly useful if normal active regeneration procedures have been interrupted or ineffective. Proper maintenance and monitoring help avoid costly failures.

DPF replacement can be done via step-by-step guides and video tutorials, which include dismantling the exhaust line and sensors. Cleaning (decoking) solutions are also available which can clear the DPF without removal, using additives or ultrasonic treatment, especially when the warning light is on.

• New DPF spare parts (e.g., CF4 X2 for 150 hp engine) are available with original-equivalent quality.
• Regular checks of exhaust temperature and pressure ensure early detection of clogging.

Choosing genuine European-manufactured parts with certified quality ensures reliable performance and environmental compliance.

The Alfa Romeo GT 1.9 JTD 150 hp version featuring the DPF may encounter clogging leading to the following issues:

• Illumination of the DPF warning light indicating clog or excessive back pressure
• Falling engine power and performance drop
• Unusual increase in fuel consumption especially during city driving
• Interrupted regeneration cycles, particularly in heavy traffic or short trips

Using compatible apps and diagnostic tools to monitor the DPF’s condition helps to anticipate and prevent serious failures.

Yes, there are original-quality DPF spare parts available online for Alfa Romeo GT diesel models, especially the 1.9 JTD engines. These parts are manufactured in Europe, certified by automotive authorities, and offered with warranties (such as 3 years / 100,000 km). Ordering online is possible with options for delivery and fitting kits. Always verify part compatibility using the vehicle VIN and engine type.

• DPF parts are crafted from stainless steel INOX 409 with high-grade ceramic monoliths
• Delivered with full technical support and installation guides for consumer and professional use

Choosing genuine European-manufactured products ensures emission compliance and durability.

To maximise the performance and lifespan of the DPF on your Alfa Romeo GT diesel car:

• Drive regularly on motorways or fast roads to ensure proper passive regeneration via high exhaust temperatures
• Avoid short trips or frequent stops that prevent full regeneration cycles
• Use suitable engine oil and additives designed to support DPF function and reduce soot buildup
• Periodically monitor DPF status with diagnostic apps to track clogging %, temperature, differential pressure, and regeneration cycles
• Consider manual regeneration or professional cleaning when advised by warning indicators
• Replace the DPF with certified original or equivalent quality parts if cleaning is not effective

Following these tips helps maintain the exhaust system in compliance with European emission standards and keeps your Alfa Romeo GT running efficiently and cleanly.

For further detailed guidance, consult Alfa Romeo GT specialised forums and video tutorials using search terms like “FAP Alfa Romeo GT 1.9 JTD regeneration” or “DPF replacement tutorial Alfa GT”.