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Home >> Acura >> 1995 >> Legend SE >> Repair and Diagnosis >> External Pages >> Different car >> Section 3 (Engine Controls - System/Component Tests) >> Idle Control System >> Engine Controls - System/Component Tests >> Fast Idle Thermovalve
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Fast Idle Thermovalve

WARNING: This page is about a different car, the 1994 Acura Legend. However, it is still accessible from the selected car via links, so may be relevant.
  1. Fast idle thermovalve opens an air passage, which by-passes throttle plate. This allows more air for a fast idle speed. Coolant warms thermovalve and closes air passage. Ensure fast idle thermovalve is closed when engine is at operating temperature.
  2. To check fast idle thermovalve, remove air hose from pipe to thermovalve. Start engine. With coolant temperature less than 86°F (30°C) and engine at idle, vacuum should be present at pipe to thermovalve. If vacuum is not present, replace fast idle thermovalve and retest.
  3. Warm engine until cooling fan comes on. Check if thermovalve is completely closed. Vacuum should not be present at pipe to thermovalve. If vacuum is present, check coolant level and for air in coolant system. If coolant system is okay, replace fast idle thermovalve and retest.
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