Fiat Stilo Diesel Particulate Filter DPF (2001-2010)

The Diesel Particulate Filter (DPF) in Fiat Stilo diesel models, especially the 1.9 JTD engine variants, captures soot from exhaust gases to meet Euro 4 emission standards. It uses a porous ceramic material such as cordierite or silicon carbide and is positioned within the exhaust system, often integrated with a catalytic converter. The DPF traps solid particles while allowing clean gases to pass through, helping reduce pollution.

The DPF functions by filtering exhaust gases through a porous structure that retains soot particles. Over time, soot builds up, increasing exhaust back pressure, which can affect engine power and efficiency. The filter undergoes periodic regeneration to burn off accumulated soot and prevent clogging. Regeneration can be passive, happening during high-speed driving at elevated engine speeds and temperatures, or active/forced with post-injection to clean heavier soot accumulations.

Signs of DPF trouble in the Fiat Stilo 1.9 JTD engines include:

• Increased diesel fuel consumption
• Loss of engine power
• Check Engine or DPF warning light illuminated on dashboard
• Reduced power output, often noticeable after higher mileage (e.g., around 198,000 km)

Other indirect causes of these symptoms can be defected injectors, cylinder compression issues, or worn seals, which may also affect DPF performance.

There are two main types of DPF regeneration:

• Passive regeneration: Occurs naturally during prolonged highway driving with engine speeds around 3000 rpm or speeds of 60-80 km/h for 15 to 30 minutes. Exhaust temperatures exceed 600°C, burning off soot deposits.
• Active/forced regeneration: Triggered when soot accumulation exceeds a threshold, causing a persistent DPF warning light. This requires intervention by a garage using diagnostic tools like VCDS to initiate post-injections and burn soot.

Each regeneration cycle typically removes 30-50% of soot but increases fuel consumption and CO2 emissions temporarily.

Recommended maintenance includes:

• Replacing the DPF between 140,000 and 190,000 km to prevent failures
• Using professional cleaning products like DPF Cleaner aerosols to maintain performance
• Ensuring regular long-distance driving to support passive regeneration
• Monitoring maximum ash weight of 60g to avoid irreversible clogging

Professional assembly is advised when fitting kits weighing around 5 kg specific to Fiat Stilo models.

A blocked DPF increases back pressure in the exhaust system, which can:

• Reduce engine power and performance
• Increase fuel consumption
• Trigger the Check Engine or DPF light on the dashboard
• Lead to engine damage if ignored due to increased exhaust pressure

It is important to address blockages promptly to maintain your engine’s health and performance.

To effectively monitor your DPF, you can use specific diagnostic apps designed for Fiat vehicles, such as "DPF Monitor - Fiat & Alfa Romeo." These apps allow:

• Tracking of soot accumulation levels
• Monitoring regeneration cycles
• Reading of engine fault codes related to the DPF system

Regular checkups with a professional garage using OBD diagnostic tools are also recommended for precise diagnostics.

Krosfou offers a 3-year WARRANTY on new DPFs for use up to 100,000 km. Conditions include:

• Installation by professional garages specialized in exhaust system replacements
• All related components such as gaskets, sensors, and injectors replaced as per manufacturer guidelines
• Proper vehicle use avoiding only short trips that prevent effective regeneration

DPFs clogged due to negligence or improper use are not covered under warranty. The warranty includes repair or replacement managed by the manufacturer’s facility in Poland.