A report from the European Commission released earlier in 2012 indicates that driving on under-inflated tyres can increase fuel consumption by as much as four percent, halve the tyre's life - and possibly kill you.The commission adds that almost five-million tons of CO2 are created by vehicles running on under-inflated rubber. SMALL CHANGE, BIG GAINSExperts have also warned that soft tyres can affect vehicle stability to the point of crashing. Bridgestone, in a survey of 38 000 vehicles across nine European countries, found 71% of cars had under-inflated tyres. European online tyre retailer Delticom provided this example: “Riding a bicycle with incorrectly inflated tyres requires much more personal energy to move the bicycle forward. The same applies to your car, using excessive fuel and creating extra CO2 emissions."Experts recommend regular tyre-pressure and tread-depth checks - at least once a month - and frequent checks of their general condition, including the spare in the boot.The tyre pressures for your car should be available on the driver’s door jamb or in the handbook.