Take the pump off and inspect it for wear or damages to the scroll and rotor, also remove the bypass valve and spring and check to make sure the bypass vale moves freely in the pump cover, no damages or gunk holding it, same thing on the end of the bypass valve and the seat in the pump cover for damage or gunk holding it from seating correctly Good luck, your making progress
Cab do you think a -12AN one way check valve would solve this problem? No room to take the pump out and its brand new .
