I have a 2013 mini cooper countryman s, it was throwing codes for low boost, after trying different solenoids decided to go ahead and replace the turbo, lines, all the usual. Now at half throttle it starts shuttering then throws the 2c56 high pressure code. I have adjusted the waste gate to where it closes with 15 inHG of vaccum it was closing around 8. Still no luck. Anybody have any tips?