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Fiddling the fuel figures

For many car drivers, fuel consumption figures are a major factor in deciding which new car to buy but a new report from campaign group Transport & Environment (T&E) suggests that manufacturers are manipulating official fuel consumption tests. For hard up motorists, the differences in claimed and actual consumption figures could blow a large hole in the motoring budget.

For many car drivers, fuel consumption figures are a major factor in deciding which new car to buy but a new report from campaign group Transport & Environment (T&E) suggests that manufacturers are manipulating official fuel consumption tests. For hard up motorists, the differences in claimed and actual consumption figures could blow a large hole in the motoring budget. Using a variety of legal, but highly dubious, 'tricks of the trade,' car makers have been claiming mpg figures that are on average 25% and sometimes even 50% better than the reality.
 
The techniques used to boost the figures are creative to say the least. Gaps between body panels are taped over to reduce wind resistance and 'super lubricants' are used to reduce engine friction. The battery is prevented from re-charging to ensure all of the engine's power is used to drive the car and tyres are over-inflated to reduce rolling resistance. Brake pads are also manipulated to reduce resistance and the car is driven in a higher gear than normal. Wheel alignment is altered to reduce rolling resistance and manufacturers also deploy slick tyres and ultra smooth track surfaces to maximise mpg. Some manufacturers have even been guilty of testing their cars at high altitude where lower wind resistance means better fuel consumption.
 
Gregory Archer who is clean vehicles manager at T&E commented: "This new evidence shows that carmakers in Europe are cheating their own customers by manipulating official tests, which leads to thousands of Euros of additional fuel costs for drivers. They are also cheating legislators, as EU laws intended to reduce CO2 emissions from cars and vans are only being met in the laboratory, not on the road. The only way to rebuild this trust is by closing loopholes in the current test procedures, to ensure that cheaters never prosper."
 
New fuel consumption tests are in the pipeline but motor manufacturers are being accused of trying to delay their introduction. The existing test is now 30 years old and is intended to represent actual road usage in Europe but T&E claim that there have been lax testing procedures and manipulation. Their report continued: "Testing and checks on production vehicles are inconsistent and inadequate, with manufacturers paying the organisations undertaking and certifying the tests. No one expected carmakers to adjust the brakes, pump up the tyres and tape up all the cracks to reduce the air and rolling resistance. These practices are now commonplace, with testing facilities being paid to optimise the results of the tests." The World Forum for Harmonization of Vehicle Regulations which administers the tests declined to comment.

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