Might have been a hose off or split, but they should have noticed that when taking it to bits.Before they rebuilt it everytime the turbo was about to boost it would judder and slow down
Michal gostinki is close to p.boro he could take a look. If you want his number pm meI don't know what they have tried but they are saying to me they need help looking at it. They have had it months and are saying they can't go any further so really need someone who know what they are doing to have a look.