I was doing some brake work on my car last week and my brother remove the master cylinder cover because I was pushing brake pistons back but he forgot to put it back on I drove around like this for days I only noticed something was wrong when my turbo was overboosting my trifecta tune is between 22 and 23 psi but it was going over 25 and the blow off valve was fluttering rapidly I don't know if this is because of a vacuum issue with the open master cylinder or what but problem went away when I put the master cylinder cover back on needless to say I need to do a complete brake system flush since I have no idea how much dirt or moisture got in there

 

u know that the reservoir is for ur brakes and for ur clutch right? did ur clutch pressure change at all?