My 2009 Mazda 6 2.2 diesel has covered 66,000 miles and is two months out of warranty. Last week I noticed a loss of power and took the car to the dealer to be inspected. After £160 of diagnostics it was reported there was a problem with the vacuum pump, which in turn has resulted in complete failure of the turbocharger.

I’m facing a repair bill of £1900 and am very unhappy, as I’ve taken good care of the car and had it serviced at a main dealer every year. Mazda have offered a 10% contribution, but that’s not enough in my opinion. Can you tell me what would have caused the turbo to fail in the first place?