Im having the same issue, i replace Booster, Master Cylinder, both calipers front, metal lines and even hoses, bleed it a couple of times no pressure is staying.
The last thing a mechanic visited me he told me it could a defective ABS also called Load Sensing Proportioning Valve (LSPV) by chat gpt
Im not understanding are u saying to switch the calipers so the bleeder is below not on the top, becuase mines are in the top, but still no brakes.
My last hopes is the ABS bellow the passenger side of car outside connected to the brake lines, since it also has the ABS and BRAKE on the dash.
HELP I ALSO AM GOING CRQZY WITH THIS SITUATION.
