Vacuum Brake Booster: Testing and Inspection

Low Or Spongy Brake Pedal
1. Worn linings.
2. Air or leaks in hydraulic system.
3. Defective master cylinder.
4. Defective wheel cylinder or calipers.
5. Improperly adjusted pedal linkage or booster pushrod.
6. Defective rear brake adjuster.
Brakes Drag
1. Improperly adjusted parking brake; binding cables.
2. Improperly adjusted or binding pedal linkage.
3. Improperly adjusted booster pushrod.
4. Defective booster return spring.
5. Sticking caliper or wheel cylinder piston.
6. Defective master cylinder.
Brakes Grab
1. Contaminated, worn or defective brake linings.
2. Drum or brake rotor out of round.
3. Defective brake booster.
Hard Pedal/Brakes Inefficient
1. Contaminated, glazed or defective brake linings.
2. Frozen caliper piston.
3. Defective vacuum pump or leak in booster vacuum supply system.
4. Defective brake booster.