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Functional Test

  1. Check master cylinder for proper fluid level and hydraulic system for leaks. Place transaxle in Neutral or Park, turn ignition off and apply parking brake. Pump brake pedal several times to eliminate all vacuum from system and hold pedal in depressed position.
  2. Start engine and allow to idle. If vacuum system is operating, pedal will tend to move downward under constant foot pressure. If no pedal motion is felt, vacuum booster is not functioning properly. Go to next step.
  3. Run engine for one to two (2) minutes and turn ignition off. Depress pedal with normal force several times. If pedal stroke is long at first and becomes shorter with subsequent strokes, booster is operating. If stroke does not become shorter, check for a damaged, restricted or improperly connected check valve vacuum hose. Repair and recheck. Go to next step.
  4. Restart engine. Depress pedal with normal force and hold pedal down. Turn ignition off and wait 30 seconds. If pedal height remains unchanged, booster is operating. If pedal height changes, check for a damaged, restricted or improperly connected check valve or vacuum hose. Go to next step.
  5. Connect a pressure gauges, vacuum gauge and a pedal depression force gauge. Bleed air from pressure gauges. Start engine. When vacuum gauge reads 19.7 in. Hg, turn ignition off. Watch vacuum gauge for 15 seconds. If vacuum gauge reads 18.7-19.7 in. Hg booster is operating. If vacuum gauge reads below 19.7 in. Hg, proceed to next step.
  6. Restart engine. Apply 44 lbs. (196 N) force to brake pedal and hold. When vacuum gauge reading reaches 19.7 in. Hg, turn off ignition. Watch vacuum gauge for 15 seconds. If vacuum gauge reads 18.7-19.7 in. Hg, booster is operating. If vacuum gauge reads below 19.7 in. Hg, proceed to next step.
  7. With engine stopped and vacuum gauge at zero, check pressure gauge. Apply 44 lbs. (196 N) force to pedal and check pressure gauge. If pressure gauges read 18 Kg/cm2 ), booster is functioning properly.
  8. Remove pedal force and start engine. When vacuum gauge reading reaches 19.7 in. Hg, apply 44 lbs. (196 N) force to pedal. If pressure gauges read 54 Kg/cm2 ), booster is functioning properly.
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