I am new to Subaru and have try'd various search's to try and identify this unit but with little success.Can any one please tell me what this unit is called and what is its purpose, my xv has a rather annoying squeak when touching the throttle pedal very lightly on and off, I have traced the squeak to this unit on the exhaust pipe but before attempting to remove itto see if I can stop the squeak  I would very much like some information on it.

 

 

Hi - looks like some form of power valve controller that changes the profile of the exhaust which removes flat spots inherent in NA engines?

 

exhaust back pressure control valve .
 

Thanks Mr B. I will remove unit and inspect as this is what I keep going to for the noise, hopefully a good clean out of the inside and flap will cure the noise.

I would suggest getting some molyslip - high temp grease. This is the stuff I use to lube the same type of valve on my motor bike