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System Test

  1. Disconnect Red-striped purge hose from throttle body, and connect to hand vacuum pump. Plug nipple on throttle body where purge hose was removed.
  2. With engine coolant temperature at 140°F (60°C) or less and engine idling, apply 14.8 in. Hg. Vacuum should hold. Raise engine speed to 3000 RPM and again apply 14.8 in. Hg. Vacuum should hold.
  3. With engine coolant temperature at 158°F (70°C) or more and engine idling, apply 14.8 in. Hg. Vacuum should hold. Turn engine off. Start engine and within 3 minutes of starting engine, apply vacuum. Vacuum should bleed down.
  4. With engine running for more than 3 minutes after starting, raise engine speed to 3000 RPM and apply 14.8 in. Hg. Vacuum should hold momentarily and then bleed down.
    NOTE: In step 4), vacuum should bleed down continuously if vehicle is at an altitude of 7200 ft. (2200 m) or higher or if intake air temperature is 122°F (50°C) or higher.
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