Infiniti EX Diesel Particulate Filter DPF (2007-2014)

The Diesel Particulate Filter (DPF) is an essential component of the exhaust system in modern diesel engines, including the Infiniti EX Diesel. It captures and reduces solid particle emissions (soot) before they exit the exhaust, helping to meet strict environmental standards such as Euro 5 introduced in 2011.

The DPF consists of a stainless steel casing containing a multilayer core made of ceramic, metal, or non-woven fabric. This porous structure features tiny channels where soot particles are trapped by forcing exhaust gases through the filter walls.

When exhaust gases flow through the filter, soot particles are trapped on the porous walls while cleaner gases pass through. Over time, soot accumulation causes increased backpressure, which may affect engine performance.

• Soot is captured in microscopic channels.
• The gas passes through, leaving particles behind.
• Accumulation increases exhaust backpressure.

Regular maintenance and regeneration are essential to avoid performance issues.

There are two types of DPF regeneration to clean trapped soot:

• Passive Regeneration: Happens automatically during normal driving when exhaust temperatures are high (e.g., highway driving at ~3000 rpm for 15-20 minutes), burning soot with the catalytic converter’s help.
• Active (Forced) Regeneration: Activated when soot accumulation exceeds a critical threshold and exhaust temperatures are insufficient. This involves a fuel post-injection to raise exhaust temperature and burn soot. A permanent DPF warning light indicates this process, requiring professional service.

Following recommended driving patterns helps optimize passive regeneration and avoid forced interventions.

Owners of Infiniti EX Diesel, especially 2012 models with 3.0D engines, may encounter:

• Engine warning light illuminated
• Reduced engine power or performance
• DPF regeneration failures causing black smoke and rough engine running

Prompt diagnosis and appropriate DPF servicing reduces risk of further engine damage.

The DPF system increases fuel consumption and CO2 emissions during regeneration cycles. Improper or interrupted regeneration might cause diesel fuel to contaminate the engine’s lubrication system, potentially leading to additional maintenance needs.

Keeping the DPF functioning correctly ensures optimal engine and environmental performance.

• Extra fuel used during regeneration.
• Higher CO2 emissions temporarily.
• Possible engine oil contamination if regeneration fails.

Following proper driving habits and maintenance routines is essential.

The DPF system provides:

• Significant reduction in fine soot emissions
• Improved air quality
• Compliance with stringent environmental standards
• Protection against hazardous cancer-causing diesel particles

This technology contributes to sustainable environmental protection while maintaining vehicle performance.

Signs of a clogged DPF include:

• Illuminated DPF warning light or engine check light
• Reduced engine power and throttle response
• Increased fuel consumption
• Black smoke from the exhaust during acceleration

If you experience these symptoms, it’s important to consult a professional for diagnostic testing and potential forced regeneration or replacement.

Regular maintenance and following recommended driving cycles help prevent clogging.