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. SpecificationsPreparation Of Tools And Measuring Equipment
Be sure that all necessary tools and measuring equipment are available starting
work. ...
Sunvisor
Use the sunvisor to shield direct light through the front or side windows.
To use the sunvisor, pull it downward. To use the sunvisor for the side window,
pull it downward, unsnap it from the bra ...
Crankshaft Position Sensor (CKPS). Troubleshooting
Wave Form
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