P1138 NISSAN - Swirl Control Valve Control System Performance
- Swirl Control Valve Control Position Sensor harness is open or shorted
- Swirl Control Valve Control Position Sensor circuit poor electrical connection
- Faulty Swirl Control Valve
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 Engine Control Module (ECM).