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Full Throttle Enrichment Function

  1. Operate engine until engine oil temperature is at a minimum of 176°F (80°C). Stop engine and connect CO tester and tachometer. Start engine and allow to idle for 2 minutes.
  2. Remove connector from double sided connector at throttle valve switch. See Figure . Slowly accelerate engine to approximately 4500 RPM. Note and record CO level reading.
  3. Bridge connections of double sided connector using Adapter (VW 1490 ). Note CO reading. Reading should increase at least 1% over recorded CO reading.
  4. If reading did not increase, check for defective wiring, engine temperature sending unit or control unit.
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