Several best-selling car brands had disparities of up to 20 miles per gallon by the end of 2013, he claimed.
VW Polos - (pictured left) one of the cars which may be affected by VW's latest admission - also had a difference of up to 20 miles per gallon.
"Miles per gallon can be directly transferred to CO2 figures and my research has already proved that VW are not the only ones gilding the lily," Mr De Nayer said.
"As a result they are all enjoying advantageous tax bands.
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VW's announcement revealed that "CO2 levels and thus the fuel consumption figures for some models were set too low during the CO2 certification process".
VW's latest confessions imply falsely declared CO2 emissions - in colloquial language, lying to the consumer, registration bodies, etc.Part Three discusses transactional agreements other than patent licenses. Goldstein is a patent attorney serving as the Assistant Director for Monitoring & Enforcement Unit in the NIH Office of Technology Transfer. • VW shares plunge as emissions scandal spreads to petrol engines • Porsche dragged into scandal as US regulator says it has found 'defeat devices' in other VW Group diesel engines • What happens if my car has VW's emissions cheating software?"For that reason, the Government is going to have no chance trying to backdate tax bills to VW as they will probably be able to prove other manufacturers were also at it."f you go back 10 years the worst offender for CO2 was very small but that has grown as the new tax laws have come in and fuel prices have gone up.