P1138 INFINITI Possible Causes
- Faulty swirl control valve control position sensor
- Swirl control valve control position sensor harness is open or shorted
- Poor electrical connection in the swirl control valve control position sensor circuit
- Faulty swirl control valve
How to Fix P1138 INFINITI Code?
Start by checking the “possible causes” listed above. Visually inspect the corresponding wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.
When is the Code Detected?
The P1138 code is detected when the target opening angle of the swirl control valve controlled by the Engine Control Module (ECM) and the input signal from the swirl control valve position sensor are not within the normal range.
Possible Symptoms
- Check Engine Light On (or Service Engine Soon Warning Light)
P1138 INFINITI Meaning
At idle and during low engine coolant temperature, the swirl control valve closes, thus increasing the air speed in the intake passage, promoting fuel vaporization and producing a swirl in the combustion chamber.
Due to this operation, this system tends to increase the combustion speed of the gas mixture, improve fuel consumption, and increase stability under operating conditions.
Additionally, except at idle and when the engine coolant temperature is low, this system opens the swirl control valve.
In this condition, this system tends to increase power by improving intake efficiency through the reduction of intake flow resistance, intake flow.
The swirl control valve is actuated by the Engine Control Module (ECM).