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Auxiliary Air Regulator

NOTE: Test must be performed on cold engine only.
  1. Remove electrical connector from auxiliary air regulator. Start engine and run at idle. Pinch either hose at auxiliary air regulator. Idle speed should drop slightly.
  2. Reconnect plug at auxiliary air regulator and warm up engine. Pinch either hose at regulator; idle speed should not change.
  3. If idle speed decreases when hose is pinched, disconnect electrical connector and connect a test lamp across terminals. If test lamp is lit with engine running, auxiliary air regulator must be replaced.
  4. If voltage is reaching regulator plug, check resistance across regulator terminals. Resistance should measure 16-22 ohms on all models. If resistance varies, replace control pressure regulator.