Hello guys. So i have a 2.7l and it lost power. No restricted performance, no fault codes, no messages on the dashboard and you can rev it above 3000rpm. You can also hear a hissing sound from somewhere around the turbo when accelerating but cant pin it down. So the mechanic says I need a new turbo, is it really the turbo or could it be a leak somewhere ? Where where sould I start looking ?