Wrxsamsti

I have and there is no significant signs, it was my first go to as Subarus are notorious for it

hey guys, i am currently having issues with my Impreza hatchback sti (ej257). as you're on throttle it builds up and as soon as you hit higher Rpm it struggles to maintain the power and it begins to lag and sounds like a rattle coming. I've not long taken the intake pipe off the turbo to check for play and there wasn't any as far as I could tell. has anyone had any similar situations that could shed some light? there is no tell tale sighs of the notorious head gasket failure but I'm losing coolant and oil but no external leaks either which make me conclude back to the turbo. My car has limited modifications as it only has a hks catback system, a GFB hybrid bov and nothing other than that so I am pretty clue less on what is going on. please help. thank you. Sam