For 1990-2009 cars

Causes | Correction
--- | ---
Damaged vacuum booster | Replace the vacuum booster.
Brake pedal linkage interference/binding | Repair/replace the brake pedal linkage.
Contaminated/improper brake fluid | Flush the brake system and repair the affected brake components.
Restricted passage in the vacuum booster | Locate and fix the source of the vacuum restriction in the vacuum booster.
Restricted brake fluid passage | Locate and fix the source of the brake fluid restriction.
Sticky caliper or caliper pistons | Repair/replace the caliper.
Parking brake not releasing | Malfunctioning parking brake lever or frozen parking brake cables.
Caliper to knuckle clearance | Repair as necessary.
Missing or weak pedal-return spring | Replace the pedal-return spring