I have been trying to find the reason that my M40 has been doing about 20mpg! on closer inspection i have a bad leak coming from the fuel hose that feeds into the bottom of the fuel filter from the fuel pipe under the car, all over hoses seem fine.
Which size hose is the replacement for this? as there is a 7.5mm a 8mm and a 9mm listed on GSF
Thanks for the link above, i've managed to get the part number which is 16121180399, but i need to know the pipe size so that i can get a quick replacement from halfords to last the weekend