Has anyone repaired the exhaust valve actuator? the little line on mine is rusted out, what have you fellas done? 1987 S4 Tii engine

 

That appears to be the turbo wastegate, it is what controls boost, if it is stuck shut, you can overboost and damage the motor. The wastegate is that can at the end, and most replacements run a rubber hose to and from it, looks like stock turbo II was metal because of heat

 

i think you could cut the bad part out, and replace with a new pipe (any hardware store sells aluminum or copper piping) and then just use hoses to connect the new part to the old part(s)