B4000 Regular Cab 4WD V6-4.0L OHV (1997)
Vacuum Brake Booster: Testing and Inspection
STEP 1
1. Push the brake pedal down.
2. Start the engine.
3. The brake pedal should move downward when engine is started.
STEP 2
1. Run the engine for 1-2 minutes, and shut off.
2. Depress the pedal three times.
NOTE: Each time the pedal is depressed the stroke becomes shorter.
3. If a problem is found, inspect the check valve, vacuum hose, and examine installation. Repair if necessary.
STEP 3
1. Start the engine and depress the brake pedal.
2. Shut engine off.
3. The brake pedal height should stay the same.
4. If problem is found, inspect the check valve, vacuum hose, and connections.