Vs ecotec air fuel ratio gauge wiring help

[Leon]

Hey guys trying to install an air/fuel ratio gauge and having trouble wiring it to the ecu. Does anyone know what colour wire it is. It's a Holden VS manual. I've wired it to a purple wire the same as the one in the O2 sensor but the gauge is reading rich only. I have 2 O2 sensors with 4 wires in each. Any help would be greatly appreciated. thanks

[Holden202T]

what exactly are you trying to do, use a 4 wire stock o2 sensor to display information on a AFR gauge ? ... if so I don't think that will work real well.

what is the brand gauge your using ?

[Leon]

Yeah how come it won't work? I'm using a auto meter.

[antus]

Because the narrow band sensor can only accurately measure 14.7:1 afr and very close too it. Generally you need a wideband sensor, wideband controller, and guage. The wideband sensor/controller usually would output the 0-5v signal the autometer guage needs.

[Leon]

Fair enough but do I have it wired up to the correct wire in the ecu?

[antus]

The ecu doesnt support wideband in factory configuration. Purple is the narrowband o2 sensor but as is it'll not read correctly and may mess with the cars ability to measure narrowband. If you leave it hooked up remember you did this if you find other problems start happening. To hookup a proper wideband controller and sensor on the vs generally you put a wideband modified memcal in and connect the controller output to the injector voltage monitor line as it was repurposed in tge wideband capable memcal.