The Air temperature sensor is used to compensate with fuel and spark timing for density changes in warm or cold air. Neglecting to wire it in may result in the engine detonating when it is Hot. Not all engines have air temperature sensors mounted on them. Most sensors were incorporated in the MAS meter. This sensor deviates plenty between manufacturers so it is difficult to cater for all manufacturers. However, it can be installed and utilized effectively. Spitronics use a 10K NTC (Negative Temperature Co efficient) resistor. It has a fixed calibration curve which is programmed in the firmware and it cannot be altered. It can however be slightly calibrated by giving it an offset percentage. The normal setting is 100%. Click on the calibrate button left of the Air sensor check box.

Reduce or increase the value to slightly shift the reading value. Do this at the critical temperature for instance where the engine is at running temperature. If the error is large you may need to replace it or get the correct sensor.
These sensors are measured at 25°C with an ohm meter to see which type it is. If you have the wrong type you may need to change the sensor to a 10K sensor. Save to ECU button will make the changes permanent.

The Air Sensor is difficult to tune as you need controlled environment to do so effectively. Cold air is denser and requires more fuel and timing. You may be required to do adjustment tuning in the winter and then in the summer. The air temperature sensor is situated just before the throttle body (if installed). Remember to enable it on the active sensors page. When the engine is used in the winter, you may advance the timing slightly as the fuel burns at a slower rate. It may even require a richer mixture for these conditions. In the hot summer the engine may tend to detonate as a hot mixture burns more rapidly and the air is thinner. Then you may require to retard the timing slightly and lean out the air-fuel ratio. Remember if you tuned in the winter or summer your graph may tend to slope just on one side.

Air Temperature Graph