Vacuum Motor Test

1985 Chevrolet Nova Base, StandardSECTION Vacuum Motor Test
  1. Remove air cleaner from vehicle. Disconnect vacuum hose from vacuum motor. Apply 20 in. Hg vacuum to motor and pinch off hose. Vacuum should not leak down more than 10 in. Hg in 5 minutes. If vacuum motor does leak down, replace it.
  2. Connect a vacuum pump to vacuum motor. Apply specified amount of vacuum to vacuum motor to open or close heated air door. If door does not open or close at specified vacuum, replace vacuum motor.
AIR CONTROL DOOR OPERATING VACUUM

Application Vacuum In. Hg
General Motors 7
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.