Our 0.6 turbo has developed a whistle; it happened suddenly but for no discernible reason. it is clearly on the induction side and varies with engine load. The garage could find nothing wrong and performance doesn't seem impaired but I'm convinced it shouldn't be there. The prospect of stripping the induction side down is scary but courtesy of COVID-19 I have more free time than usual. I wondered if anyone was familiar with this problem and might know where I should look. Many thanks David H
A slight whistle is normal as the turbo spins up and produces boost, however, if it becomes unusually loud then the turbo may be worn or not getting proper lubrication. There could also potentially be a leak somewhere creating the whistle sound.