does this fail? could it be the cause of my slow pickup? Im replacing the hoses this weekend
it does fail yes. but slow pickup could be caused by VNT's being stuck.
Easy way to check is to strip down to the point where you can see the turbo. get some vacuum on the line directly to the line that sits on the VNT actuator, or if you can, push and pull against the rod. if it does not move it means the vanes are stuck. It is easy to strip down and clean them if you know how, but I have heard about some stuff you can spray in that removes all the build up around them. Where I live we do not get this spray and I have loads of turbo knowledge so I just strip them down and clean them.
If however you experience this due to the vanes being stuck, it usually comes with a underboost/overboost error aswell.
So I suggest you rather diagnose each bit before stripping it down. Check vaccum lines, turbo play, the actuator movement as mentioned and even boost leaks and also EGR if it is JTD, JTS afaik does not have EGR.