im having the exact same issue after driving my car home! up the motorway turbo kicked in then eng mgnt light then no boost in 4th.

great round the doors but soon as im out need to hit 4th it does it again. the eng mgnt light is stuck on code p02099
en engine malfunction on the screen

i have a 2009 1.6 tdci titanium with 78000 on the clock

i hope this is my fix! need to check those pipes?