In the great days of Ealing comedies, Alastair Sim and Terry-Thomas, the idea of a diesel-powered Jaguar would have caused many a moustache to bristle in outrage. No self-respecting black-and-white era bank robber would have accepted an oilburner under the bonnet of his Mk2. Diesels were for lorry drivers, and that was the end of it. 

However, when Jaguar did finally bite the derv bullet in 2003 they made a very good fist of it. Or rather, parent company Ford in cahoots with PSA Peugeot Citroen made a very good fist of it. They needed to as well because premium European cars had already made the diesel jump, brilliantly rehabilitating the engines that were once the pariahs of the motor industry.

This week’s shed is a 2006 XJ TDVi from bang in the middle of the X350 production run. The important thing to remember about the X350 was its high-tech aluminium body structure that chopped around 40 per cent out of the weight of the preceding XJ, revolutionising the way the car drove – and it already drove well – without frightening off the Jag traditionalists with revolutionary styling. 

It wasn’t about the specs on XJs, it was about their unique feel on the road. For the spec hounds though the TDVi did the 0-60mph run in the high sevens, 141mph flat out and 35mpg at the pumps, a pretty useful set of numbers for a luxury saloon and practically unbelievable for those who remembered the earlier V12-powered XJs whose idea of a pleasant surprise was to return 12mpg rather than 8mpg. 

The miles aren’t low on this XJ at 166k but the body looks as crisp as the crease in Shed’s crimplene trousers, with tight shut lines and no apparent blemishes. Shed assures you that the drive experience will be really good, the 204hp twin-turbo 2.7 diesel doling out a creamy 321lb ft of torque at just 1,900rpm.

Where do they go wrong? Electronics are a weak point and the engine did get a reputation for spinning its main bearing shells. It will use a drop of oil too as it ages, but when properly looked after it’s a reliable lump that will go on to 200k or more. If you’re smelling diesel in the cabin it’s probably leaking flexi joints on the cats. A Jaguar dealer will try to lure you in for new cats at predictably vast expense, but the wise owner will choose to look online for conversion pipes that take the place of the busted flexi pipes. 

You’ll certainly want to see written evidence of two or ideally three cambelt changes and of several gearbox fluid/filter changes. In general terms DPFs and EGRs can clog up in diesel cars with high-performance potential but which are instead pootled about the place in Driving Miss Daisy fashion. As usual in these cases, Shed recommends the Italian tuneup, a service he is delighted to provide on the bypass for those villagers who have made the mistake of buying big Jags, big Mercs and the like. Again generally, injectors can leak and turbos can give up but that’s the same for any car. 

This XJ has been sitting around on the PH classifieds for a while now. It may be worth letting it sit for a few days more too because by the time you’re reading this, the MOT will either have expired or will be on the point of doing so. The next test will be interesting. The only advisories on last July’s cert were for one worn rear tyre, one worn front brake pad and two corroded rear brake pipes. If that’s the only corrosion on the car this time around, that will be a major bonus and/or miracle because the sills on these XJs are about as good at resisting rust as Shed is at resisting the village postmistress, i.e. not very. 

It’s fashionable now to write the XJ off as an old man’s car, but old men can have fun too and Shed knows that the VP would love a hide-enriched ride in this Sov. The long-wheelbase version would have suited Shed better. They were a lot kinder to the knee joints of late-night rear seat ‘occupants’ (as opposed to passengers) than regular XJs like this one. XJ parking sensors were notoriously sensitive too, going off at the merest suggestion of tiny objects approaching dangerously from the next county, or possibly as a consequence of certain rhythmic vibrations from the back seat area that did not form part of the Jag’s NVH development process.

Note the asymmetric cupholders. In a different universe a long time ago Shed would have ventured the thought that these were to hold a pint glass for sir and a glass of wine for the lady, but one of the PH bigwigs made him go on an awareness training course earlier this year so thankfully those days are long gone.