Vito 112 cdi 2001 - loss of power

[VitoVoom]

Help guys 'n gals! Always went like a rocket from new, then a couple of weeks ago, sudden loss of top end power during a journey? Still completely smooth, quiet, no smoke and can coax her to 70 but no guts to pull out and away, especially not uphill. Visually viewed turbo turbine via exhaust and it's nicely smooth and free spinning. Wastegate is open when engine off and can be closed by thumb pressure against some sort of spring in the actuator. Should I be checking that the pump is making adequate vacuum? How much vacuum should there be? Can I read this at the convenient tee where the main vacuum line enters the brake servo? All advice gratefully received. Martin

 

[Grant12]

Try turbo should still be the problem I had the same thing on my vito twice they came out and done somthing on a laptop then it was fine again.but its not that the turbo has gone it only took him about 10 minutes.
Hope this helps