Citroen Grand C4 Picasso Exhaust: Buy Genuine & Aftermarket Parts

It depends how much of it you are replacing. A full system on a C3 or comparable model generally lands between R8,000 and R18,000. Individual sections are far cheaper — a silencer runs R2,400-R5,400, and a catalytic converter R4,450-R11,750 depending on whether it is a petrol three-way cat or a diesel oxidation catalyst. Fitting adds roughly R1,400-R2,950. In practice most owners never replace a whole system; they replace the section that has rusted through.

From the engine backwards: the manifold, which collects gas from the cylinders; the catalytic converter or diesel oxidation catalyst; the oxygen or lambda sensors that tell the ECU how combustion is going; a particulate filter on diesel models; then the resonator, silencer and tailpipe for noise. Diesel Citroens also carry the additive system that supports particulate filter regeneration, which is one of the more commonly misunderstood parts of the setup.

Typically 80,000-150,000 km, but location matters more than mileage. Coastal salt air shortens it considerably and short urban trips shorten it again, because the system never gets hot enough to dry the condensation out of the back box. That is why the rear silencer almost always goes first. Stainless sections last longer than mild steel and are worth the difference if you are on the coast and intend to keep the car.

You should not. A leak forward of the cabin can let carbon monoxide in, which is the serious version of the problem and not something you can smell reliably. Beyond safety, a car with a blowing exhaust will not pass roadworthy, excessive noise is a traffic offence, and a leak upstream of a lambda sensor makes the ECU fuel incorrectly, so you lose economy as well. Small holes are usually a cheap section repair if you catch them early.

Because of what is inside them. Cats contain platinum, palladium and rhodium, and the scrap value on a single unit runs from a few hundred to a couple of thousand rand. They can be cut out of a parked car in a couple of minutes, and South Africa is now a global hotspot for it. If you are replacing one, keep the invoice for roadworthy and insurance purposes, and a shield or clamp is worth considering if the car parks on the street.