Variable swirl control actuator consists of DC motor and motor position sensor(potentiometer) which detects the position of swirl valve.
As closing one intake port out of two at idle and below 3000RPM, swirl effect is taken on intake air. This swirl effect increases air flow rate.
However, because air flow rate is too high, swirl effect is neglectable thus, swirl valve is opened for efficient intake of air.
To prevent swirl valve and shaft form being stuck by foreign metarial, and to learn max opening and closing position of swirl valve, it is fully opened and closed twice at turning engine OFF.
? Swirl
The air flow which indicates Intake air swirls with respect to the axis passing through the centre of piston with length-direction by intake port which is eccentric from the centre of combustion chamber.
P2009 is set when open or short to ground in variable swirl actuator driving motor (+) output terminal. The polarity of (+) and (-) lines shift each other in accordance with the condition of swirl valve(opened or closed) thus, checking both (+) and (-) circuits is required.
Item
Detecting Condition
Possible Cause
DTC Strategy
Voltage monitoring
Variable swirl valve motor circuit
Enable Conditions
Engine running
Threshold Value
Short to ground in motor output terminal
Open in motor circuit
Diagnostic Time
1000ms
Fail Safe
Fuel Cut
NO
Swirl valve opened at variable swirl control actuator failure
EGR Off
Fuel Limit
Check Lamp
Fig.1) Waveform when variable swirl valve closed at idle. Channel A is (+) and B is (-).
Fig.2) Waveform when variable swirl valve opened at above 3000RPM. Channel A is (-) and B is (+).