Citroen C4 Picasso Exhaust System: Specs, Fitment & Common Faults
On the C4 Picasso, a genuinely honest fact: the DPF additive never burns off, meaning even excellent driving habits can't prevent an eventual, expected filter service.
Illustration for editorial purposes
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OEM Part Number: confirm via VIN — Rear silencer (aftermarket) Bosal 190-063 / Walker 23228
| Rear silencer (back box) — aftermarket | Bosal 190-063; Bosal 190-363 (accessories needed); Walker 23228 (960 mm); Walker 23391 (980 mm); Walker 71210 (820 mm); Walker 71213 (810 mm) (all sold without attachment parts) |
|---|---|
| Centre / intermediate silencer — aftermarket | Bosal 135-371; Bosal 135-465 (accessories needed); Walker 01489 (code 52, 750 mm); Vegaz CS-11 (940 mm); MTS 01.57810 (740 mm, trim-code limited) |
| Front pipe / catalytic converter (DPF on diesels) — aftermarket | or DPF: HJS 96 21 5006 (Euro 4/5/6a/6b); BM Catalysts BM91785H (Euro 6, with FK91785); BlueKat 1007050 (500 mm, with manifold); Walker 28100 (code 91, 330 mm, with manifold); NAP CAK10515 (Euro 5, EP6CDT/N18B16A) |
| Genuine (OE) numbers quoted | None quoted in catalogue listings — order genuine parts against your VIN |
| Fitment notes | Petrol, diesel and diesel hybrid listed at category level only |
A Genuinely Important, Honest Fact: Good Driving Habits Alone Won't Prevent Eventual DPF Service — Citroen C4 Picasso Exhaust System
It's worth knowing something distinct from the usual "just drive faster to regenerate" advice: diesel particulate filters on this platform rely on an additive (commonly referred to as Eolys, or cerine) injected into the fuel to help the trapped soot burn at a lower temperature during regeneration. This additive itself, however, never burns off — it accumulates as a genuine ash residue inside the filter permanently, regardless of how well the car has been driven. This means even a diesel driven mostly on motorways with excellent regeneration habits will eventually need the DPF professionally cleaned or replaced simply due to this ash buildup, typically somewhere in the region of 100,000-120,000 miles — this isn't a fault or a sign of poor maintenance, but a genuine, expected part of diesel particulate filter technology.
If you're chasing a specific EGR-related fault, real fault codes worth knowing include P0401 (insufficient EGR flow) and P0405 (EGR position sensor signal fault) — worth mentioning to whoever is diagnosing the car, since these point toward different specific parts of the system.
Citroen C4 Picasso Exhaust System: The Part That Announces Its Own Problems
On the Citroen C4 Picasso, this is one part where you'll usually hear the fault before you see it — a rattle, a drone, a sudden increase in noise that wasn't there last week. That's actually useful, since it gives you a head start on catching problems early.
Citroen C4 Picasso Exhaust System: Watch: Replacing It
Plain C4 (not Picasso); earlier-generation platform, weak match
Citroen C4 Picasso Exhaust System: What It Does
The Citroen C4 Picasso's exhaust system channels burnt gases away from the engine, reduces noise through the silencer, and treats emissions through a catalytic converter and particulate filter before gases exit the tailpipe. Petrol and diesel versions often use entirely different systems due to different emissions treatment requirements.
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Citroen C4 Picasso Exhaust System: Warning Signs, DIY Difficulty & Aftermarket Advice
These are the same regardless of make or model — see our full Exhaust System Guide for warning signs and fault codes to watch for, confirming fitment against your VIN, and which aftermarket brands are worth trusting.
More Citroen Exhaust System
The same part, covered across other Citroen models.