Volkswagen: vw jetta turbo, vw jetta, vw tdi

Question
I have a 2000 vw tdi jetta. It has about 140K miles, and has been a very good car up to now.  I noticed that it would bog down sometimes and then the turbo would kick in, but in changing gears again it might or might not have what feels like a dead spot.  I have had the fuel fiter changed and that did not correct the problem.  Also all the connections have been checked and seem fine.  A couple of days ago, I lost the power of the turbo altogether, however we do not think that the turbo is actually bad.  My mechanic, not big on vw's, says that the manifold looks dirty, but we have not done anything to that yet. The air filter was checked and is OK. I certainly want the easiest solution, low on funds. haha

Answer
1) Has the turbo been making any kind of 'whining' or grinding sound in the last couple of months while running.

2) When did the car have it's last complete tune-up?  (Including a fuel injection cleaning)


We need to start here first.


Keep me posted.  Don't worry, we'll figure it out.


Ron