Hi, I know this is a ford site, However I also have a Mazda 6 diesel and when driving along it surges, it has done 300 thousand, I have had it to Mazda, they said they put it on the machine but nothing is wrong with it, I took mechanic for a ride and he said yes there is something wrong but we can not work it out, Does any one with experience know what the problem could be, I have hade fuel treatment done, DPF cleaned, had something in the front of motor where it soots up, had that cleaned, yet still surges, to me it is a fuel delivery problem but you would have thought the dyno or what ever they use at Mazda would have shown up something. If any one has a clue, and needs more info let me know, or if you are on the gold coast I can let you have a drive. The car goes very well when you put the foot down.

Thanks