Originally Posted by
Scoff
Are you using the analogue output for something else james ? P4 will simulate a NB probe without disrupting the wideband display on the gauge.
But if your using the white wire already, and you don't want to install a second boss then you could fudge up a variable voltage on the narrow band input for the ECU.
Find a 5v output on the ECU, maybe the 5v that feeds the TPS or map sensor, then find a ground (from the same sensor will do) and feed those to either side of a 4.7k pot. (volume control, with 3 pins, you know the sort of thing). The middle pin from the pot can be fed to the narrow band input on the ECU. Then, you should be able to set the pot so there's abotu 0.7v on the wiper (output, middle pin). In theory you should just be able to turn the idle closed loop fueling up or down by twiddling the pot !
That's a real bodge mind, and not a piece of advice I'm particularly proud of *lol*