Do our Jaguar X-Type diesels have DPFs and how do they work?

When my wife's 12-year-old BMW needed replacing she was delighted to acquire an 18-month-old Jaguar X-Type diesel. The car joined my own 9-year-old petrol X-Type, which is still going strong after 120,000 miles. The new car had a myriad of small but useful improvements but, being a diesel, the 47mpg against 30 for the petrol and lower road tax made it a dead cert. That is until I read your Q&A column mentioning something I had never heard of - the dreaded particulate filter.

I am at a loss to understand how accumulated gunge can somehow end up requiring a dual mass flywheel (whatever that is) and some other expensive parts. Would you tell us a little more please? Do some cars not have particulate filters? Are small diesel engines worse or better than large ones? If one drives the car out of the garage to retrieve the lawnmower and then back in again is that disastrous? Would a 100-mile round trip on the motorway burn off the filtered particles from earlier short drives or not?

Asked on 4 June 2011 by ML, Leeds

Answered by Honest John
No worries, neither the X-Type Jaguar diesel, nor the Mk III Mondeo diesel on which it was based, ever had a diesel particulate filter. The dual mass flywheel is entirely different. That is a device designed to cushion torque reactions between the engine and the clutch and gearbox. DPF = Diesel Particulate Filter. DMF = Dual Mass Flywheel. Your Jaguar will have a dual mass flywheel. It’s never ever a good idea to start any car engine just to move the car a short distance. Best to push it.
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