GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2000 🢒 Firebird 🢒 Brakes 🢒 Hydraulic Brakes 🢒 Hydraulic Brake Diagnostic System Check

Symptom

Causes

Improper Brake Pedal Travel
    • Leaking brake line or connection. Refer to Hydraulic Brakes.
    • Leaking piston seal. Refer to Disc Brakes.
    • Leaking master cylinder (internal). Replace master cylinder.
    • Air in brake system. Refer to Hydraulic Brake System Bleeding .
    • Contaminated or improper brake fluid. Refer to Brake Fluid and Brake Fluid Handling .
    • Leaking vacuum or booster system. Refer to Hydraulic Brakes.
    • Damaged vacuum booster. Refer to Power Vacuum Brake Booster Replacement .
    • Uneven brake lining wear. Refer to Disc Brakes.
    • Brake lining damage by abuse. Refer to Disc Brakes.
    • Improper thickness variation in rotor. Refer to Brake Rotor Thickness Variation Check .
    • Excessive lateral runout in rotor. Refer to Brake Rotor Lateral Runout Check .
    • Brake assembly attachments loose (including splash shield).
    • Improperly adjusted stoplamp switch or cruise control vacuum dump. Refer to Stop Lamp Switch Adjustment .
    • Incorrect vacuum booster pushrod length.
    • Low brake fluid. Refer to Master Cylinder Reservoir Filling .
    • Improper rear brake adjustment.
    • Low engine vacuum.

Brake Pedal Travel Gradually Increases
    • Leaking brake line or connection. Refer to Brake Fluid Leak .
    • Leaking piston seal. Refer to Brake Caliper Overhaul .
    • Leaking master cylinder (internal). Replace master cylinder.
    • Restricted passage in the vacuum booster.
    • Damaged vacuum booster. Refer to Power Vacuum Brake Booster Replacement .
    • Restricted brake fluid passage.

Excessive Brake Pedal Effort
    • Leaking vacuum or booster system.
    • Restricted passage in the vacuum booster.
    • Damaged vacuum booster. Refer to Power Vacuum Brake Booster Replacement .
    • Worn out brake lining.
    • Glazed brake lining.
    • Incorrect brake lining material.
    • Contaminated brake lining.
    • Brake lining damage by abuse.
    • Improper rotor surface finish.
    • Restricted brake fluid passage.
    • Brake pedal linkage interference or binding.
    • Operator riding the brake pedal.
    • Low engine vacuum.
    • Excessive vehicle loading.
    • Rotor corroded.

Excessive Braking Action
    • Damaged vacuum booster. Refer to Power Vacuum Brake Booster Replacement .
    • Worn out brake lining.
    • Uneven brake lining wear.
    • Incorrect brake lining material.
    • Brake lining damage by abuse.
    • Improper rotor surface finish.
    • Scored rotor. Refer to Brake Rotor Refinishing .
    • Brake assembly attachments loose (including splash shield).

Brakes Slow To Respond
    • Air in the brake system. Refer to Hydraulic Brake System Bleeding .
    • Contaminated or improper brake fluid. Refer to Brake Fluid and Brake Fluid Handling .
    • Leaking vacuum or booster system.
    • Restricted passage in the vacuum booster.
    • Damaged vacuum booster. Refer to Power Vacuum Brake Booster Replacement .
    • Glazed brake lining.
    • Restricted brake fluid passage.
    • Brake pedal linkage interference or binding.
    • Sticking caliper or caliper pistons. Refer to Brake Caliper Overhaul .
    • Low engine vacuum.

Brakes Slow To Release
    • Contaminated or improper brake fluid. Refer to Brake Fluid and Brake Fluid Handling .
    • Restricted passage in the vacuum booster.
    • Damaged vacuum booster. Refer to Power Vacuum Brake Booster Replacement .
    • Restricted brake fluid passage.
    • Brake pedal linkage interference or binding.
    • Sticking caliper or caliper pistons. Refer to Brake Caliper Overhaul .
    • Parking brake not releasing.
    • Caliper to knuckle clearance.

Brakes Drag
    • Contaminated or improper brake fluid. Refer to Brake Fluid and Brake Fluid Handling .
    • Brake lining damage by abuse.
    • Excessive lateral runout in rotor. Refer to Brake Rotor Lateral Runout Check .
    • Brake assembly attachments loose (including splash shield).
    • Restricted brake fluid passage.
    • Improperly adjusted stoplamp switch or cruise control vacuum dump. Refer to Stop Lamp Switch Adjustment .
    • Brake pedal linkage interference or binding.
    • Incorrect vacuum booster pushrod length.
    • Loose front suspension parts.
    • Operator riding the brake pedal.
    • Sticking caliper or caliper pistons. Refer to Brake Caliper Overhaul .
    • Parking brake not releasing.
    • Caliper to knuckle clearance.
    • Improper rear brake adjustment.
    • Parking brake cables seized.

Uneven Braking Action (Side to Side)
    • Contaminated or improper brake fluid. Refer to Brake Fluid and Brake Fluid Handling .
    • Worn out brake lining.
    • Uneven brake lining wear.
    • Glazed brake lining.
    • Incorrect brake lining material.
    • Contaminated brake lining.
    • Brake lining damage by abuse.
    • Improper rotor surface finish.
    • Scored rotor. Refer to Brake Rotor Refinishing .
    • Brake assembly attachments loose (including splash shield).
    • Restricted brake fluid passage.
    • Incorrect front wheel alignment.
    • Incorrect tire pressure.
    • Loose front suspension parts.
    • Sticking caliper or caliper pistons. Refer to Brake Caliper Overhaul .
    • Parking brake not releasing.
    • Caliper to knuckle clearance.
    • Rotor corroded.

Uneven Braking Action (Front to Rear)
    • Leaking brake line or connection. Refer to Brake Fluid Leak .
    • Leaking piston seal. Refer to Brake Caliper Overhaul .
    • Leaking master cylinder (internal). Replace master cylinder.
    • Air in brake system. Refer to Hydraulic Brake System Bleeding .
    • Contaminated or improper brake fluid. Refer to Brake Fluid and Brake Fluid Handling .
    • Worn out brake lining.
    • Uneven brake lining wear.
    • Glazed brake lining.
    • Incorrect brake lining material.
    • Contaminated brake lining.
    • Brake lining damage by abuse.
    • Improper rotor surface finish.
    • Scored rotor. Refer to Brake Rotor Refinishing .
    • Brake assembly attachments loose (including splash shield).
    • Restricted brake fluid passage.
    • Sticking caliper or caliper pistons. Refer to Brake Caliper Overhaul .
    • Low brake fluid. Refer to Master Cylinder Reservoir Filling .
    • Improper rear brake adjustment.
    • Excessive Vehicle Loading.

Scraping Noise from Brakes
    • Worn out brake lining.
    • Uneven brake lining wear.
    • Contaminated brake lining.
    • Brake lining damage by abuse.
    • Brake assembly attachments loose (including splash shield).
    • Loose front suspension parts.
    • Rotor corroded.

Brakes Squeak without Application
    • Worn out brake lining.
    • Uneven brake lining wear.
    • Glazed brake lining.
    • Incorrect brake lining material.
    • Contaminated brake lining.
    • Brake lining damage by abuse.
    • Scored Rotor. Refer to Brake Rotor Refinishing .
    • Improperly adjusted stoplamp switch or cruise control vacuum dump. Refer to Stop Lamp Switch Adjustment .
    • Incorrect vacuum booster pushrod length.
    • Sticking caliper or caliper pistons. Refer to Brake Caliper Overhaul .
    • Caliper to knuckle clearance.

Brakes Squeak During Application
    • Worn out brake lining.
    • Uneven brake lining wear.
    • Glazed brake lining.
    • Incorrect brake lining material.
    • Contaminated brake lining.
    • Brake lining damage by abuse.
    • Scored rotor. Refer to Brake Rotor Refinishing .
    • Brake assembly attachments loose (including splash shield).
    • Excessive vehicle loading.

Brakes Chatter (Roughness)
    • Scored rotor. Refer to Brake Rotor Refinishing .
    • Improper thickness variation in rotor. Refer to Brake Rotor Thickness Variation Check .
    • Excessive lateral runout in rotor. Refer to Brake Rotor Lateral Runout Check .
    • Brake assembly attachments loose (including splash shield).
    • Loose front suspension parts.
    • Out-of-balance wheel assembly.
    • Improperly torqued wheel nuts.
    • Rotor corroded.
    • Grease or dirt on the rotor.

Brakes Groan at the End of Stop
    • Incorrect lining material.
    • Contaminated brake lining.
    • Brake lining damage by abuse.
    • Grease or dirt on the rotor.

Brake Warning Lamp ON
    • Leaking brake line or connection. Refer to Brake Fluid Leak .
    • Leaking piston seal. Refer to Brake Caliper Overhaul .
    • Leaking master cylinder (internal). Replace master cylinder. Refer to Master Cylinder Replacement .
    • Air in brake system. Refer to Hydraulic Brake System Bleeding .
    • Contaminated or improper brake fluid. Refer to Brake Fluid and Brake Fluid Handling .
    • Parking brake switch circuit grounded.
    • Parking brake not releasing.
    • Low brake fluid. Refer to Master Cylinder Reservoir Filling .

Premature Lining Wear
    • Leaking brake line or connection. Refer to Brake Fluid Leak .
    • Incorrect lining material.
    • Brake lining damaged by abuse.
    • Improperly adjusted stoplamp switch or cruise control vacuum dump. Refer to Stop Lamp Switch Adjustment .
    • Brake pedal linkage interference or binding.
    • Incorrect vacuum booster pushrod length.
    • Operator riding brake pedal.
    • Sticking caliper or caliper pistons. Refer to Brake Caliper Overhaul .
    • Parking brake not releasing.
    • Caliper to knuckle clearance.
    • Improper rear brake adjustment.
    • Excessive vehicle loading.
    • Parking brake cable seized.

Parking Brake Won't Hold
    • Worn out brake lining.
    • Uneven brake lining wear.
    • Incorrect lining material.
    • Contaminated brake lining.
    • Brake lining damaged by abuse.
    • Improper rotor surface finish.
    • Sticking caliper or caliper pistons. Refer to Brake Caliper Overhaul .
    • Parking brake cables seized.

Parking Brake Won't Release
    • Sticking caliper or caliper pistons. Refer to Brake Caliper Overhaul .
    • Parking brake cables seized.

Brake Pulsation

    • Incorrect lining material.
    • Contaminated brake lining.
    • Brake linings damaged by abuse.
    • Scored rotor. Refer to Brake Rotor Refinishing .
    • Improper thickness variation in rotor. Refer to Brake Rotor Thickness Variation Check .
    • Excessive lateral runout in rotor. Refer to Brake Rotor Lateral Runout Check .
    • Loose front suspension parts.
    • Out-of-balance wheel assembly.
    • Improperly torqued wheel nuts.
    • Rotor corroded.

Brake Pulls
    • Worn out brake lining.
    • Uneven brake lining wear.
    • Incorrect lining material.
    • Contaminated brake lining.
    • Brake linings damaged by abuse.
    • Improper rotor surface finish.
    • Scored rotor. Refer to Brake Rotor Refinishing .
    • Restricted brake fluid passage.
    • Incorrect front wheel alignment.
    • Incorrect tire pressure.
    • Loose front suspension parts.
    • Sticking caliper or caliper pistons. Refer to Brake Caliper Overhaul .
    • Caliper to knuckle clearance.
    • Rotor corroded.