Hard Pedal

An internal bind or a failed vacuum check valve would cause this condition. Refer to Decreasing Brake Pedal Travel to test power brake unit for an internal bind. To check for a failed vacuum check valve proceed as follows:
1. Start engine and increase engine speed to approximately 1500 RPM, then close throttle and stop engine.
2. Wait 90 seconds, then try brake action.
3. If brakes are not vacuum assisted for two or more applications, replace check valve.