Waste Gate Actuator
From WikiLEC
This is the wastegate actuator...
Turbo and wastegate mechanism
It bolts to the turbo housing via three bolts (position indicated by the green arrows). The capsule (yellow arrow) converts pressure/vacuum to linear motion in the actuator rod (red arrow) to turn the wastegate shaft (purple arrow) thereby controlling the amount of exhaust gasses by-passing the turbo and ultimately controlling the level of boost.
File:WastegateStickingFigure1.jpg
Turbo and wastegate mechanism
The wastegate often sticks and needs releasing.
