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Full-Load Enrichment Test

  1. Disconnect wiring between throttle valve switch and ECU. Check resistance of throttle valve switch at male plug. In idle speed position, resistance should be infinity. In full load position, resistance should be zero ohms. If readings are not correct, replace throttle valve switch. If readings are correct, go to next step.
  2. Connect meter adapter cable to differential pressure regulator. Set multimeter to mA scale. Bridge connector of throttle valve switch that connects to ECU. Turn ignition on. Current reading should have constant nominal value of 7-9 mA. If current reading is correct, test is complete. If current reading is not correct, go to next step.
  3. Check wiring between ECU and differential pressure regulator for continuity. Resistance reading should be zero ohms. If reading is correct, replace ECU. If reading is not correct, repair short in wiring.
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