van wont restart

[doderz2014]

Hi all. New to the form so excuse the noob details.

Have a mk7 2.4 turbo Deisel. It will start first time once it's been sitting a few hours. However if I'm driving and say stop for a second and try to restart it won't. It shows plenty of power but just won't start. It's been plugged in and no codes. Fuel filter was quite dirty and that got changed. We are all baffled by this and any info would be excellent. Hope to hear from a guru soon.

Many thanks.