This is nothing to do with caravanning, but I wonder if any of you car experts can give me an answer. I have just taxed my wife's nearly new Vauxhall Corsa Design Auto 1400cc three-door and was surprised to be charged £150 for the year - the rate for cars with 166-185 Co2 emissions. Checking in What Car, I see that the three-door model of this car indeed is listed with an emission rate of 178, whereas the five-door model of exactly the same car is only 142 which would only cost £100 to tax. In fact, all the Corsas are around 142 and only this three door model shoots up so dramatically. Anyone know why?