Vacuum Booster Diagnosis Hard Pedal
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
DEFINITION: Brake pedal effort is too high when stopping. | ||||
1 | Inspect for a damaged, collapsed, loose, or open vacuum hose. Is the vacuum hose OK? | -- | ||
2 | Repair or replace the vacuum hose. Is the brake pedal effort too high when stopping? | -- | ||
3 | Inspect for a faulty vacuum check valve or a leaking grommet. Is the check valve and the grommet OK? | -- | ||
4 | Replace the check valve or the grommet. Is the brake pedal effort too high when stopping? | -- | ||
5 | Inspect for a loose or plugged vacuum fitting. Is the vacuum fitting OK? | -- | ||
6 | Clean, tighten, or replace the vacuum fitting. Is the brake pedal effort too high when stopping? | -- | ||
7 | Replace the vacuum brake booster. Refer to Power Vacuum Brake Booster Replacement . Is the brake pedal effort too high when stopping? | -- | Go to Brake Pedal Excessive Effort . | |
8 | Verify proper brake system operation. Does the brake system operate properly? | -- | System OK | |
Vacuum Booster Diagnosis Brakes Grab
Step | Action | Value(s) | Yes | No | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
DEFINITION: The brakes grab on and off. | ||||||||||||
1 | Inspect the hydraulic brake pipes and hoses. Are the hydraulic brake pipes and hoses damaged? | -- | ||||||||||
2 | Replace the hydraulic brake pipes and hoses as necessary. Refer to the appropriate procedure: Do the brakes still grab? | -- | System OK | |||||||||
3 | Inspect the fluid level in the master cylinder. Is the fluid level low in the master cylinder? | -- | ||||||||||
4 | Fill the reservoirs with the proper brake fluid. Check for leaks. Do the brakes still grab? | -- | System OK | |||||||||
5 | Inspect the master cylinder seals. Are the master cylinder seals faulty? | -- | ||||||||||
6 | Repair or replace the master cylinder seals as necessary. Refer to Master Cylinder Overhaul . Do the brakes still grab? | -- | System OK | |||||||||
7 | Inspect the master cylinder casing. Is the master cylinder casing cracked? | -- | ||||||||||
8 | Replace the master cylinder. Refer to Master Cylinder Replacement . Do the brakes still grab? | -- | System OK | |||||||||
9 | Look for leaks in the following components:
Do any of the components leak? | -- | ||||||||||
10 | Inspect and repair the leaking components as necessary. Do the brakes still grab? | -- | System OK | |||||||||
11 | Inspect for air in the hydraulic system. Is there air in the hydraulic system? | -- | ||||||||||
12 | Bleed the hydraulic system. Refer to Hydraulic Brake System Bleeding . Do the brakes still grab? | -- | System OK | |||||||||
