Just got a fresh built 28 Ford truck. It has new discs all the way around with new MC & booster.With the motor off I have great pedal after bleeding. When I start the motor the pedal goes way down and sticks there. Almost like the booster is not working. The hose to the booster is pluged into the intake but the modulator valve to the tranny is also pluged in the same place. Would this cause the booster not to work. Or is my new booster bad. thanks in advance for any help.