CATCH-CANS: Can of worms, more like it. Car-makers don’t like them, some mechanics don’t understand them and four-wheel-drive owners who have them fitted tend to love them. So what’s the reality? Do you need one? Will it wreck your engine? Will it void your warranty? Will it save the day, or even the planet? Let’s break it down.
HOW DID THE CATCH-CAN COME ABOUT?
THE catch-can was initially developed for stationary diesels and the trucking industry. As recreational four-wheel-drives have become more reliant on common-rail diesel technology, so has the catch-can debate become a hot-button topic.
WHAT’S THE PROBLEM, ANYWAY?
TO ANSWER that, you need to understand what’s happening inside the modern-diesel engine. Essentially, pollution laws around the world (including here) have meant a certain percentage of the engine’s exhaust has to be directed back into the combustion chambers so the
