I replaced my master cylinder and booster with chrome ones. I bench bled the M/C. When I run the engine, (no foot on the brake pedal) the booster pulls the brake pedal down and locks up the calipers on the front brakes. Shutting down the engine will let the pedal return to normal after a minute or so. One of my neighbors, who is not really a brake guy, says my booster is bad. Ideas??? Thanks!