I only first found out about it via diesels. Especially when I limped into a garage and was told the turbo had failed and how much it would cost for them to replace it. I went home decided to see if I could get it off from under the car without removing too much - only to find that a circlip had gone missing and the actuator link had come loose at one end. I pushed it back on and fitted a new circlip and normal service was resumed.