Citroen C4 Picasso Diesel Particulate Filter DPF

The DPF on Citroën C4 Picasso diesel models (such as 1.6 HDi 110 hp or 2.0 HDi 163 hp) captures fine particles from exhaust gases. It regenerates by burning accumulated soot at high temperatures, aided by a cerine additive that lowers the combustion threshold to effectively clean the filter.

The DPF tends to clog quickly with urban use at low speeds (<100 km/h), as regeneration requires engine speeds above 3000 rpm and driving at speeds over 100 km/h for 10-30 minutes, typically on highways. Symptoms include warning lights such as "Risk of DPF clogging" or "Emission system fault," loss of power, engine hesitation, black smoke, increased fuel consumption, and frequent regeneration phases (~every 500 km).

To maintain the DPF, consider the following:

• Passive/Active Regeneration: Drive for 30 minutes at over 3000 rpm on the highway for self-cleaning or use diagnostic tools (e.g., Diagbox for PSA) for forced regeneration.
• Check the cerine additive reservoir, which often empties around 180,000 km; refilling prevents false clogging warnings.
• Hydrogen decarbonization can clean the DPF, EGR, and turbo intake, reduce fuel consumption and emissions, restore power, and prevent costly failures.
• Be aware that a clogged DPF can damage injectors or turbo components; prioritize highway driving if the filter is partially saturated.

Regular preventive maintenance including additive refills and periodic forced regenerations can prolong DPF life.

DIY cleaning or removal (located under the vehicle after the turbo) includes:

• Disconnect hoses, marking their positions for reassembly.
• Loosen 4 bolts (size 13 wrench, with penetrating oil and extension bars for hard-to-reach bolts behind the catalytic converter).
• Remove the DPF, perform oxygen or hydrogen cleaning, then force regeneration using a diagnostic tool.

The process takes about 1-2 hours for an experienced DIYer. Note the risk of turbo damage common in some PSA models and follow specific video tutorials available for 2.0 HDi 163 hp and 1.6 HDi 2007 engines.

At dealerships, replacing the DPF typically costs between €1200 and €1500, including the EGR valve and pressure sensors. Aftermarket alternatives are available ranging approximately from €232 to €324, compatible with various engines such as the 1.6 TD HDi DV6TED4/F 110 hp (1560 cc, from 03/07 onwards). Post-replacement, DPF initialization via diagnostic tools is necessary.

The cerine additive pouch (additive reservoir) can be replaced DIY in 30-60 minutes even on models with pneumatic suspension like the 1.6 HDi 2007 Exclusive. Steps include disconnecting the battery, removing 4 screws from the cover, and replacing the pouch with a genuine Citroën part ordered from dealerships.

Maintaining this additive system helps prevent false clogging warnings and extends the DPF’s life.

If the DPF becomes significantly clogged (around 76% saturation at high mileage like 185,000 km), it can lead to damage of the fuel injectors or turbocharger. You may still be able to drive for a few hundred kilometers, but should prioritize longer highway trips to enable regeneration and avoid further damage.

DPF systems have sensors that can detect clogging levels and trigger warning lights but typically do not provide precise ash content or soot percentage readouts directly to the driver. Diagnostic tools used by professionals can measure the approximate saturation level and ash content for accurate assessment and maintenance planning.

Regularly testing and monitoring the DPF using diagnostic equipment is recommended to avoid costly failures and maintain system performance.