Citroen C4 Picasso H-Pipe

Exhaust work on these cars falls in the R2,400 to R9,800 band through the specialists in our network, and an H-pipe section on its own sits at the lower end of that. The first thing to establish, though, is whether your car has one — most Citroens sold here do not. Send the model and engine code and we will confirm the layout before quoting anything.

A deep drone or a rasp under load is the characteristic one, usually with a slight flatness below 3,000 rpm. The reason is that the crossover exists to balance pressure pulses between the two banks, so once it is holed the banks are no longer talking to each other and the scavenging the system was tuned around stops working. Consumption creeping up without a fault code is the other common report.

Section-by-section replacement through fitment centres runs R2,400 to R9,800 depending on the material, the length of the run and how many mount points have to be fabricated. Stainless costs more up front and lasts several times longer in coastal conditions, which is the comparison worth making on a car you intend to keep. Mild steel makes sense on a car you are about to sell and very little sense otherwise.

Pro Citroen Spares and the exhaust specialists in our network can supply or fabricate the section. On a crossover pipe, fabrication is usually the better route — a competent shop will bend and weld one to your car's exact mounting points for less than a factory section costs, and can build it in stainless while they are at it. Get a quote for both before committing.

Condensation, mostly. Every litre of fuel burnt produces water, and on short trips the exhaust never gets hot enough to drive it out — so it collects in the lowest, most horizontal part of the system, which is exactly what a crossover is. The pipe then rusts from the inside outward, and salt air accelerates it sharply. Coastal owners can expect a crossover to go at around 80,000 km; a car doing long open-road runs will see far longer.