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Home >> Ford >> 1981 >> Cutaway 4.9L Eng VIN E >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> MCU Engine Control System >> Diagnosis & Testing >> Functional Test >> Engine Running Test
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Engine Running Test

  1. Start engine and raise speed to 2500-3000 RPM within 20 seconds after start. Hold RPM until 3 initial pulses appear. Continue holding speed until code pulses begin (10-40 seconds).
    NOTE: If more than 3 initial pulses occur, go to test 14 to check for an open circuit in the tachometer signal.
  2. Return engine to idle when codes begin. Codes will be repeated once. Record codes, then stop engine and reconnect canister purge hose. Refer to code chart to locate appropriate test.