On my sons 1996 Grand Prix, we replaced both front rotors complete, and the right rear rotor complete due to my son's complaint of grinding, and finding 2 of the rotors not releasing. After the work was through including bleeding system, including front and rear ports on the anti lock brake control cylinder, the car has a stiff normal brake pedal while the engine is off, but when the engine is started the brake pedal goes all the way to the floor, and will not stop the car. While setting at idle in park, when you press the brake pedal the engine begins running rough. Could this be failure of the vacuum booster unit? Thanks for any assistance.
Oct 25, 2009 at 11:30 PM