Diesel Particulate Filter introduced for petrols
Despite the heavy criticisms that have been directed at diesel engines in the past few years, the fuel still offers advantages. Recently, I liaised with a committee that influences the UK government’s air quality policies, which recommends the diesel scrappage scheme (of which I do not approve, as written here).
I queried, if people scrap their diesel cars, with what should they be replaced? I was told that modern ‘cleaner’ direct-injection petrol engines (or hybrids) hold the answer but, when I pointed out that such units have been found to be more than 2,000 times more polluting in particulate emissions than older petrol engines, the supposed expert could not provide an alternative practical suggestion.
Slightly ironically, it appears that Volkswagen has provided some kind of solution, by introducing some of its petrol engines with a particulate filter. Some readers may gasp in horror, citing the lack of understanding about particulate filters fitted to diesel cars and many problems have been reported about the units clogging prematurely. However, as petrol engines tend to achieve higher combustion temperatures than diesels, I suspect that this will be less of a worry, unless very short journeys only are covered, perhaps.
Volkswagen expects to fit more particulate filters to its petrol models in the coming years and we have also heard that other manufacturers are due to roll-out their own filters, shortly. We shall provide more technical information, when it becomes available.