I thought I would try Shell V-Power diesel. At a Shell Garage I saw a logo in red with a V-Power sign on it and filled up from the pump showing the red V sign. This was the only one on the forecourt. Obviously this was misleading as on enquiring, after the car started misfiring, I was told that I had put petrol into my diesel Ford Fusion. The AA sorted out the problem for me very efficiently. After the AA man had gone through all the cleaning processes, which took just over an hour, he put a can of diesel additive - Common Rail, by Wurth.UK limited. Could you advise me whether it would be better to use this additive or the V-Power, bearing in mind I am retired and 82 years old. Obviously the cost of either has some bearing.