hey my mind has gone blank and cant think of the life of me what it does can any one help me on here please

 

Can be many things. http://en.wikipedia.org/wiki/Actuator

Are you asking about a wastegate actuator on a turbo?

Read this -

http://www.motorsport-developments.co.uk/actuators.html

 

yeah i am mate just want it in simple terms really

 

It actuates (opens) the wastegate at a predetermined pressure, this in turn lets more exhaust gas out via the exhaust which slows the turbo down, this is done for two reasons, A) So the turbo does not overspeed and B) Stops overboosting.

Martin