Helpdesk

THIS WEEK: Dealing with diesel filters

From AS: I bought a diesel Skoda Octavia RS in 2008 as I was tempted by the lower VRT and motor tax. I've owned a diesel car before so had no problems with this. Or so I thought. The car is great but I immediately discovered you have to ignore the on-board computer information guiding you on how to drive to achieve fuel efficiency. The warning light for the particle filter came on within a week and the only solution is to take the car on a long drive down a motorway and drive it hard with the revs up around 3,000rm. You need to do this for about 15 minutes after the warning light goes off to clear it. As I do a lot of city centre driving/short runs this was happening regularly until I learnt to drive it around town in a lower gear than I would normally drive. Once I left it for a few days after the warning light came on but a more serious warning message came up to take it to the workshop and the car went into "safe" mode with a top speed of 80km/h. I might be a bad case as I do mostly short runs of 2-3 miles as I live close to town and this just doesn't suit the car. I manage it by driving in a lower gear around town. (i.e. keep the revs up close to 2,000). I now know that virtually all diesel cars have this filter. So when I come to change I have absolutely no doubt that I'll go for a petrol - if someone will sell me one.

Several weeks ago a reader raised his concerns about diesel particle filters (DPF) fitted to cars that are used largely for town driving. Since then we have received lots of emails on the matter, most along the same lines as yours. A spokesman for Skoda said this was not a general problem with the Octavia RS and they have since been in contact through the dealership to have the car inspected. However, while there may be a specific issue with your car, the issue of DPFs causing problems for owners who never really take their diesel-powered cars out of the urban traffic is an increasing issue. It's one that may well see more urban motorists considering petrol once more, or perhaps making the great leap towards hybrid or electric.

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