hi i was wondering who is authorised to control petrol stations? i would like to make a complaint about a petrol station because a full tank of diesel shows 400+ miles on my van how ever the other day (i think it was a bp station) i filled up the tank again and it was around 300 miles and it really hardly made to 300 miles! i will be glad if any one gives me number i can call to take further action as 50-100 miles difference is what i had only!...