P1138
DTC P1138 SWIRL CONTROL VALVEDescription
SYSTEM DESCRIPTION
Swirl control valve has a valve portion in the intake passage of each cylinder.
While idling and during low engine coolant temperature, the swirl control valve closes, Thus the velocity of the air in the intake passage increases, promoting the vaporization of the fuel and producing a swirl in the combustion chamber.
Because of this operation, this system tends to increase the burning speed of the gas mixture, improve fuel consumption, and increase the stability in running conditions.
Also, except when idling and during low engine coolant temperature, this system opens the swirl control valve. In this condition, this system tends to increase power by improving intake efficiency via reduction of intake flow resistance, intake flow.
The swirl control valve is operated by the ECM.
COMPONENT DESCRIPTION
Swirl Control Valve
Swirl control valve consists of actuator and valve. The valve is installed in the intake manifold, and the actuator is connected to the rear end of the valve shaft.
The swirl control valve uses a step motor which has four winding phases. It operates according to the output pulse signal of the ECM. Two windings are turned ON and OFF in sequence. Each time an ON pulse is issued, the valve opens or closes. When no change in the control position is needed, the ECM does not issue the pulse signal. A certain voltage signal is issued so that the valve remains at that particular opening.
Swirl Control Valve Position Sensor
Swirl control valve position sensor is installed on the intake manifold. The sensor is connected to the front end of the valve shaft of the swirl control valve.
The sensor responds to the valve shaft movement. This sensor is a kind of potentiometer which transforms the swirl control valve position into output voltage, and emits the voltage signal to the ECM.
Consult-II Reference Value In Data Monitor Mode:
On Board Diagnosis Logic
Malfunction is detected when the target opening angle of swirl control valve controlled by ECM and the input signal from swirl control valve position sensor is not in the normal range.
Possible Cause
- Harness or connectors
(The swirl control valve circuit is open or shorted.)
- Swirl control valve
- Harness or connectors
(The swirl control valve position sensor circuit is open or shorted.)
- Swirl control valve position sensor
DTC Confirmation Procedure
NOTE: If "DTC Confirmation Procedure" has been previously conducted, always turn ignition switch "OFF" and wait at least 10 seconds before conducting the next test.
With CONSULT-II
1. Turn ignition switch "ON" and wait at least 2 seconds.
2. Select "DATA MONITOR" mode with CONSULT-II.
3. Start engine and let it idle for at least 10 seconds.
4. Turn ignition switch "OFF" and wait at least 10 seconds.
5. Turn ignition switch "ON" and wait at least 2 seconds.
6. Start engine and let it idle for at least 10 seconds.
7. Maintain engine speed at about 2,000 rpm for at least 10 seconds.
8. Turn ignition switch "OFF", wait at least 10 seconds and then turn "ON". If 1st trip DTC is detected, go to "Diagnostic Procedure" below.
If 1st trip DTC is not detected, go to next step.
9. Perform step 5 through 8 three times.
With GST
Follow the procedure "With CONSULT-II" above.
EC-SWL/S-01:
Wiring Diagram
Diagnostic Procedure
Diagnostic Procedure Step 1 - 3:
Diagnostic Procedure Step 4 - 6:
