Hi if you want the Redneck solution try a gallon of paint thinners the lunatic AKA Scotty Kilmer on youtube absolutely loves it and Hates Audis, maybe its his secret plan to rid the U.S. of the brand, the design of the EGR system is to say the least peculiar but I have no doubt Mrs Merkel and co were obviously euphoric when they came up with this little number, at least BMW had the sense to put the cooler on the side of the engine at the top so at least us have a go brigade were in with a chance, Audis propensity for over engineering is breathtaking, Scotty on the other hand just keeps churning out videos on how to kill your car and the walking dead love him for it.
Steve.