About a month ago the turbocharger on my 2012 Holden Colorado with the 2.8 CDTI engine started to whistle at low revs and take off. The dealer tells me it's fine, but I find it hard to believe that it would just start to do it after 11 months and about 25,000km. What do you think?
No there appears to be something amiss with it, so get the dealer to check it again. If that doesn't resolve the issue take it to an independent diesel engine mechanic and have them check it for you.