The Haltech Quicktune feature is a feature that helps to automate the tuning process by performing the comparison between target AFR and measured AFR, and then performing the appropriate injection time adjustment.

The Haltech Quicktune feature can be used only if the ECU has a calibrated wideband O2 Sensor input setup. The calibrated wideband O2 input will be the output of an external wideband O2 sensor product such as the Haltech wideband O2 controller. Other wideband controllers that have a 0-5V calibrated output are also acceptable. The INNOVATE, FJO, AFX, M&W Ignitions, TECH-EDGE and many other Wideband O2 controllers have this capability.

Once an auxiliary input has been correctly setup and calibrated with a wideband O2 sensor input (go to the setup menu -> sensor setup -> calibrate sensors -> wideband O2 controller to adjust the wideband O2 sensor calibration) the target air to fuel ratio table can be setup. This table is found in the ECU Navigator tree, under :

With a correctly configured wideband O2 sensor input and the target AFR map set to the desired air to fuel ratio, the Quicktune feature is ready to be used. To use the Quicktune feature, select the fuel base table that you wish to tune. With the fuel table selected pressing the "Q" key on the keyboard activates Quicktune and adjusts the fuel map value for the current load point the engine is operating at. The ECU compares the actual AFR as measured by the wideband O2 sensor to the desired AFR as set in the target AFR map. The ratio of these values is used to increase or decrease injection time by an amount proportional to the difference in AFR's.

It is important to note that when the Q button is pressed, the ECU only makes an adjustment to the load and RPM point the engine is actually operating at, regardless of the number of mapping points you may have selected. For this reason best results are achieved when the RPM and load points are in the middle of a map cell when the Q key is pressed.

Tapping the Q button multiple times in quick succession will yield poor results as the system will apply multiple corrections before the first changes are relayed through to the wideband O2 sensor. Instead, to reach your target AFR as quick as possible, hold the load and RPM as close to the centre of the targeted cell as possible and press Q, then wait for the measured AFR to stabilise to the new AFR before pressing Q again.

The Quicktune function is limited to ±30% of change for a single key press.

Pressing the 'W' key copies the calculated Quicktune injection value into the next load cell to the right of the current load cell and the same two corresponding cells in the next RPM range.