Kia Optima: RCV Control Solenoid Valve. Description and OperationWhen the throttle is closed, while the engine is running at cruise rpm (tip-out), the turbocharger boost pressure raises rapidly. The pressure wave strikes a compressor blades causing a knocking noise. To prevent this the ECM opens the recirculation valve which allows excessive boost pressure to vent back to the air cleaner side of the turbocharger compressor.

Adjustment
RCV Control Solenoid Valve. SpecificationsRefrigerant line. Repair procedures
Replacement
1.
Discharge refrigerant from refrigeration
system.
2.
Replace faulty tube or hose.
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Repair procedures
If the there is lack of power, excessive oil consumption or poor fuel economy,
measure the compression pressure.
1.
W ...
Seat Belt Buckle Switch (BS). Components and Components Location
Components
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