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Home >> Acura >> 1988 >> Legend Base, 2D Coupe, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> EGR System >> Component Testing >> THERMOVALVE >> Legend Carbureted
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Legend Carbureted

  1. With coolant temperature less than 131° F (55° C), disconnect vacuum hose No. 19 at thermovalve. Using a hand-held vacuum pump, apply vacuum to thermovalve port. Vacuum should not hold. If vacuum holds, disconnect air cleaner bleed hose from thermovalve. If vacuum bleeds off, check for restriction in hose or at air cleaner. If vacuum does not bleed off, replace thermovalve.
  2. Start engine. Disconnect air cleaner bleed hose at thermovalve. Disconnect vacuum hose No. 19 at thermovalve. Connect vacuum gauge to No. 19 hose. Increase engine speed to about 3000 RPM. Verify presence of vacuum. If vacuum is not present, check for defective check valve or restricted orifice. Also check for plugged vacuum port at carburetor.
  3. Allow engine to idle. Reconnect hose No. 19 to thermovalve. Connect vacuum gauge to air cleaner thermovalve fitting. Increase engine speed to about 3000 RPM. With coolant temperature less than 131°F (55°C), vacuum should show on gauge. Disconnect vacuum gauge.
  4. Allow engine to reach operating temperature (cooling fan comes on). Reconnect vacuum gauge at thermovalve bleed fitting. Vacuum should not show on gauge. If thermovalve does not react as specified, replace thermovalve.
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