posted 2 years ago

Safety Charity Warns Common Modifications Risking Lives

Garages Illegally Removing Diesel Particulate Filters

The Institute of Advanced Motorists has claimed that “quick fix” vehicle modifications could cost lives. The road safety charity is particularly concerned by three common changes: the removal of the diesel particulate filter, fitting xenon headlights and reprogramming/chipping the electronic control unit. A motorist might remove his/her filter as it could prove troublesome and expensive. Risk of failure increases if the car tends to be driven in town as this can prevent the filter reaching the necessary temperature to self-clean. Motorway speeds tend to be more beneficial. A filter reduces the pollutants that emerge from the exhaust so it must be present if originally fitted (by law). Some garages, however, will remove it even though – as of January 2014 – this should lead to MOT failure. The Institute of Advanced Motorists Head of Technical Policy, Tim Shallcross, said that removal: “isn’t a task that can be done accidentally as it involves reprogramming the engine management computer.” He continued: “Unscrupulous traders still offer to cut the case open from the top of the unit, remove the filter, and weld it shut in an attempt to pull the wool over the eyes of the tester to achieve an MOT pass.”  Shallcross added: “They are selling a service that's killing people”.

Xenon Headlamp Conversions And Chipping Cause Concern

The Institute of Advanced Motorists is concerned about xenon headlamp conversions too. This arrangement can – according to the road safety charity - “dazzle oncoming traffic” as it lacks the self-levelling function. This could cause an accident which is a hefty price for having fashionable lights. Mr Shallcross said: “Fitting this kind of lighting is illegal” and emphasised that: “claiming ignorance of the law is no excuse”. Finally reprogramming a vehicle's electronic control unit is a popular modification that can increase performance. It typically involves plugging a laptop into the diagnostics port then uploading software to adjust the fuelling, drive-by-wire throttle response, turbo control, engine load and torque limiters. However, Shallcross stressed that: “No after market warranty company will offer to cover a car that has been chipped.” Furthermore: “If you don’t tell you insurer it is likely to invalidate your policy but - if you do tell your insurer - he could refuse to cover your car or could demand a hefty increase to your premium.” It could also devalue the car and make it harder to sell. Best leave it alone, ey?


All points considered I would think that poor road conditions and too many foreign drivers with little or no knowledge of UK traffic systems are probably harming more people than a removed dpf or xenons.

I remapped my Discovery 3 and gained 45bhp and instead of having 24mpg I now get 28mpg on short local journeys and was 27mpg on motorways to now 33mpg, its not used as a Chelsea tractor either it's used as a Service vehicle to my Haulage Company, and by remapping our lorries a 2mpg improvement was obtained, and however much people dislike lorries our lorries transport all your food to the shops. Better fuel consumption means less pollution its not rocket science but there again MP's are not Brain Surgeons ether. [Do they have a brain???!!!! ]

A more worrying modification that is being carried out is the lowering of suspensions and the fitting of over size wheels and tyres, drivers are adjustin the steering geometry to geg the wheels and tyres to fit inside the bodywork giving no thorght to the movement required on the steering and suspension as can be observed on some cars where the sidewalls of the tyres have rubbed trought to the brading of the tyre carcase, these car ane normaly presented for an mot test with a set of standard rims fitted and the refitteds with the oversized tyres when the car has passed its mot.also the fitting of oversied tyres witll render the speedometer inaccurateto a considderable degree

I think Andy misses the point of DPF its to remove carcinogenic material from the exhaust its not really about smoke

Disappointed that this article comes from advanced motorists. As with any business when these things are done properly there isn't a problem. Dpf removal with a remap, passes the mot smoke test? If the smoke level in the test is the problem then change the test. Badly adjusted lights, Hid or not are a problem.....and they are included in the MOT test. Remaps? Again if they are done properly......what is a problem is the way some people drive; and poor driving is not dependent on having Hid, a dpf removal and a remap. Perhaps the AIM needs to think more about the causes of road safety. What is that saying 'it's a poor workman who blames their tools'

I think there is to much emphasis that all vehicle modifications are bad and that drivers who do modify their cars are an increased risk to the public. The HID/Xenon upgrades i agree with, its like looking into the sun sometimes when you see a car fitted with them. They are illegal as cars that have these lights must have self leveling and washer jets. The ECU blueprinting/remaps dont all specialise in increasing performance some maps are designed with mpg and emission control in mind. There is a small majority of driver that are out there who do give the ''modifying scene'' a bad name but you've got to remember that the vast majority of drivers investing money into their cars are going to want to look after it and not cause any damage towards it

Agree with all previous comments as an advanced driving instructor & fleet driver trainer I gave up my IAM membership reluctantly as I found some of the letters in their magazine from alleged advanced drivers were embarassing and could quite frankly be answered by learner drivers could the IAM Head of Technical Policy Tim Shallcross please let us know what experience and professional qualification certificates he has.

The comments here tell you everything as to why the IAM are concerned about these subjects. The ignorance of the majority of contributors is truly a cause for concern that we have to coexist with people so wilfully damaging the health of everyone they pass. Moreover it IS a legal requirement to have both self levelling suspension and headlamp washers with HID. Without both the vehicle contravenes Construction and Use regulations; for the reason that it is unsafe for oncoming motorists.

I have recently changed my car from a 2006 Lexus GS300 to a 2013 Lexus GS250. * years improved engine technology? My older vehicle averaged 32-35 mpg, this updated and smaller engine averages 27-29mpg. I am told I can have it "chipped" for £150 and if I don't see an improvement in consumption within one month I can have a full refund. On 15,000 miles per year it's no contest!

what a load of drivel did manufacturers tell people about the so called dpf filter and how it works I DONT THINK SO, do buses or trains have these fitted and they run daily nightly no they use ultra low sulphur the same as diesel cars with an additive injected at loading terminal before being delivered as for lights if it says 45 watts or 55 then it is legal for our roads also these chips do more good than harm as they make an engine run far better more fuel efficient so what do you say to that mr turniphead

What a load of rubbish. Trying to increase the click count with titles like this, only to pad your article with drivel about remaps. I actually agree about the HID kits in non projector/adjustable lights, and the DPF removal although the way you've portrayed it is verging on sensationalist, not to mention the remapping is well off the mark. It's just the typical branding of 'modifications are dangerous' and 'car enthusiasts and modifiers are all out to kill your children and ruin our roads'. Complete b0ll0cks.

Utter rubbish from wheel shufflers anonomis. Projector xenons with self levelling still dazzle traffic at times but xenon technology market or aftermarket is 10 times safer than halogen. Remapping provides a bespoke setup particular to the car, the driver and the environment which is invaluable for cars which have been mass produced. I say again ignore the above.

HID's with no leveling system can dazzle people? Well no shit, so do the thousands of other normal lights that the moronic sheep drivers off this country can't be arsed to adjust. Self levelling is also not a mandatory or legal requirement, so how about a bit of fact checking first before writing this drivel?

I'm not often stirred to write on these sort of web sites but the previous comments are very worrying. Removing the particulate filter releases small particles of soot and other contaminates from the cars exhaust. They are very fine and when breathed in can be trapped in the lungs and eventually cause cancer or some other undesirable lung disease. Not a problem in the country but in a crowded city it's not good. Xenon headlights are a real pain. The article is quite correct they do dazzle when the vehicle fitted with them is approaching and they can be just as annoying when you are being followed by a car fitted with them. They never seem to dip sufficiently and the cut off is not at all sharp as it is with the correct headlight bulb. It's worrying to think that I share the roads with such ignorant and churlish people as the previous commenters. Come on people the world doesn't revolve around you have some consideration of others.

Utter bullsh1t. Who is this Stephen Turvil? Was he set up to write this article? I noted he hasn't commented on the comments.

What is their problem? This isn't killing anyone. Re chipping the car is a good thing, you can get out of it the performance you payed for and if you often race it on the track. They should care more about what were bein charged for insurance! An a 23 year old I'm still pay £3000+ a year on a Golf GTI...

Up until I read this tripe I always believed the IAM was a sensible body. Now they are the Institute of Asinine Morons

Can someone please explain why removing the DPF would result in death? Shallcross added: “They are selling a service that's killing people”.

Another key benefit of remapping is improved fuel consumption - noticeably absent from this tideous article. Our Ford Kuga does an extra 5 miles to the gallon now - does this make me a life-risking hooligan?

How about they just leave us alone, eh? What a silly article, I think they need to look more into the profits being made by insurers year on year while still increasing premiums to a point where it is so unaffordable that we have thousands of uninsured drivers on our roads....

As a member of the Institute of Advanced Motorists, my opinion is that its not the business of the IAM to be commenting on this kind of subject. The IAM is all about promoting road safety through better driving is it not? Well, thats the reason I took their test and drive according to the rules of the road. My car is modified, my insurers know about it, of course, they relieve me of a few quid more each year too, but there is nothing unsafe or illegal about my car. Frankly, I've had enough of all the "do gooders" and politically correct busy bodies meddling in our lives, and dictating how we live. Enough is enough.

If that is so why do companies like Merc and Audi offer these as power upgrades/performance packs and they offer de-limiters for top speed at a premium?

"No after market warranty company will offer to cover a car that has been chipped." - What a load of rubbish. The chipping/remapping companies often cover existing warranties on cars themselves and a professional remap company should only remap the ECU within the cars existing limits. As for insurance, increases are often reasonable. And finally you can get a remap removed from your car and set back to the default settings should you come to sell the car. I guess the article really should stress the importance of using reputable remapping companies and informing insurance of changes.