looking at threads on this forum and elsewhere, have got fed up with people phoning me up asking the same questions time and time again, and thought I would post the definitive rules. Thanks to Trevd01, Dave Pumford, and the VW owners club for much of this info.The band that your vehicle falls in to is based on the date it was first registered in the UK, NOT the date it was manufactured.
The emissions test at your MOT has ABSOLUTELY NOTHING TO DO with your CO2 rating for road tax purposes.
Look at your V5 document. In Part 4, Vehicle Details, if your “Taxation Class” is shown as “Motor Caravan”, then you will pay £185 up to 31 March 2009, and £200 from 30 April 2009. It does not matter if you have a CO2 figure on your V5 or not. The exception to this rule is where your vehicle was originally registered in the UK as a Car or Light Goods Vehicle, and the vehicle has been re-registered as a Motor Caravan, then you will pay duty as if you are still a car (see below). HOWEVER, you should note that if you are registered as a Motor Caravan, and you do not have a full camper conversion, and you are subjected to a roadside or VOSA check, your vehicle may be confiscated and even crushed!
If you are not registered as a Motor Caravan, and a CO2 figure is shown in Part 4 of the V5, you will pay £400 up to 31 March 2009, and £440 from 30 April 2009. This is based on a CO2 figure of 302 gm/km. Different rates may apply for later model petrol Bongos.
If you are not registered as a Motor Caravan, and no CO2 figure is shown in Part 4 of the V5, you will pay £185 up to 31 March 2009, and £200 from 30 April 2009.
And that’s it. Until it changes again.
, just checked mine and its registered as PLG, but no emissions are written on my V5 
