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. SpecificationsSeat belt restraint system
WARNING
For maximum restraint system protection, the seat belts must always be
used whenever the vehicle is moving.
Seat belts are most effective when seatbacks are in the upright position.
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EPB connector input/output
Pin No.
Function
Pin No.
Function
1
-
21
Gear switch
2
-
22
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Recommended SAE viscosity
number
CAUTION
Always be sure to clean the area
around any filler plug, drain plug, or
dipstick before checking or draining
any lubricant. This is especially
important in dusty or sandy areas
and ...