Boosting later...

[Steffgj]

The turbo on my 1.9tdi (AWX) is suddenly not kicking in until around 2000rpm where as it used to kick in nearer 1600rpm. Suddenly feels really sluggish.

The only thing I've changed are the vacuum hoses to 3mm silicone. Could the smaller diameter have this affect? Cleaned the MAF yesterday with no change.

 

[S4_dan]

You need to do some logs via VCDS to see what the maf readings are and boost logs are. Cleaning a maf won't fix a faulty maf but it will improve if it's a dirty maf.

It could be that you have a boost leak hence the delay in build up of boost.