Hi Guys, the bro in law has an auto twin turbo legacy and is having this issue and I have no idea what could be causing it, when he starts the car its all fine but as soon as he goes into drive and press the accelrator the car revs but doesnt move and than suddenly it will move and than it will start to work fine, reverse works fine and if you just have it in D without pressing the accelrator car moves normal, also when he accelrates you hear this weird sound from the front right like a air suction or something like soft metal grinding but in idle and rev nothing... put on a diagnostic and came up with no error codes.... any ideas??