Having owned a diesel BMW X5 for the past twelve years (about the same length of time as I have subscribed to Diesel Car), and having recently tried most of the competitors, I am about to take delivery of a new BMW X5 xDrive30d which I intend keeping for hopefully ten years for private, mixed, local and motorway use. I was alarmed to see on last night’s Watchdog that the X5, with its keyless entry system, is easily stolen. Although BMW assures me that it will come with the latest security software update, I want to ensure that when I park it at Heathrow that it will still be there when I return a couple of weeks later. Other than fitting a steering wheel clamp, do you have any suggestions? The new car meets Euro 6 emissions, so can you give me any information regarding any potential issues regarding EGR, DPF, catalytic converters, or other gadgets which may cause any issues later on, including tips on how best to avoid them and have trouble-free motoring? What about using Miller’s Ecomax, and is there really any difference in quality between supermarket and service station diesel? Excellent magazine and your ‘Back to Basics’ series and other practical independent advice is most helpful. Regards,
Thomas Lloyd, Hereford

Hello Thomas, “I was alarmed…” you write. Oh – very droll! I’m not an expert on outwitting security systems, but I know that the latest methods involve a careful window break-in at an alarm blind-spot and access to the OBD port. I would imagine that BMW is working 24/7 to update systems to outsmart this apparently crude but effective method. When or before you take delivery, I would make contact and ask BMW what the latest situation is. You would have a possible warranty problem if you were to attempt any additional electronic theft prevention, but research led me to this website www.securemycar.co.uk in London, whose best method to me seems to be a technique of physically immobilising the OBD port when the car alarm is armed. Take a look at their website.

Otherwise, I go along with your steering wheel lock proposal, but you need to park nose-in to a wall, if at all possible, and then turn the wheels to full lock before fitting the lock, to prevent any possibility of the car being towed away with the front wheels lifted! I hesitate to offer any advice on steering wheel locks though, as there are often fitting problems, so I would visit a big Halfords and make sure anything fits before you buy, or purchase on a sale or return basis. The Stoplock brand is well spoken of, and I’ve seen good words about the HG-134-66 Airbag 4X4 steering wheel lock that should fit an X5.

I’ve written quite a lot recently about supermarket fuel, and said that I either buy good branded diesel, but never the overpriced super stuff like BP Ultimate and Shell Nitro Plus or whatever it’s called, or buy supermarket fuel and add Millers. But I would leave it alone for a thousand or two miles anyway, as you don’t want to slow down the running-in process. When the engine is settled in a bit, do your own experiments and see if you notice any difference. Unless you do lots of short runs, any good fuel will keep your fuel system and injectors clean, but you might benefit from the Cetane Value improver in Millers – see another letter in this issue.

Regarding your new X5, you should find that alongside your fuel filler you have a filler for Adblue urea-based additive that eliminates NOx emissions using Selective Catalyst Reduction. It involves injection of small quantities of the additive, but the tank lasts for tens of thousands of miles, so is nothing to worry about; in fact it’s a far better way of controlling NOx emissions than some of the other methods that only just about scrape under the EU6 limits. To avoid any engine problems with DPF and EGR, all that you really need are fairly frequent runs of say 15 miles or more at open road speeds to keep things in good shape. If you or your wife do have spells with lots of short runs, then maybe a blast every now and again is indicated. But should you (it’s unlikely) get any amber dashboard warnings regarding emissions control, don’t just ignore them. If you do get one, read the handbook, but it probably only tells you to do what I just have – to take it out for a bit of a blast and a decent long run, to blow the cobwebs away and get the DPF to do a regeneration, after which all will be well. Good luck with the new car!

Thomas replied…

Thank you very much for your quick and helpful response. What does OBD stand for and I am told that there is a simple way of preventing access to it. Is it situated under the bonnet, or in the car and what does it look like? I will certainly be checking it all out with the BMW dealer when the car arrives. Regards,
Thomas

OBD stands for “On Board Diagnostics”. It is where they plug in to every service to read any faults or stored information. It’s usually under the dash or down in the footwell. It will be somewhere down near your knee, to the left or right, or possibly where your knee would be on a left-hand-drive car! I did find this apparently easy trick to defeat OBD port intrusion: “Just remove one of the CAN bus wires from your J1962 OBD socket. The wires push backwards out of the plastic connector by pushing down a little locking tab. Then just tape said wire back onto the loom with a bit of electrical insulating tape.” I’m not sure I would want to do a DIY job like this though on a nice car like an X5.
Doc