Cars registered on or after 1st March 2001 pay one rate of VED and those before that date pay a reduced amount. Is the actual registration date the critical thing, or would the build date, if it was, say, 1st Feb 2001, have any significance?
It's also judged on the cars individual Co2 levels.
For example, my Mum has a 1.4 TDi Polo. According to Parkers/Autocar etc,it should be on the Â£35/year category. However, because our particular car emits 1g/km more than the manufacturer stated figure (according to the V5) it's in the category up!
Jake, that might be a particular variant of the 1.4tdi rather than your actual car. I've seen something similar, the Skoda Roomster 1.9tdi is a band D. But most actually seem to be E, though I was pleasantly surprised the one we bought was a D. It will be down to something like whether you had the optional aircon or not, or even if you had a real spare wheel instead of the tub of goo and a pump. Certain models of cars, like skoda greenlines and vw bluemotions you aren't allowed to order a real spare wheel to keep the weight and therefore emissions in the right class.