Replacing OEM Narrowband O2 with Wideband O2 question

[varrien]

Hi, I'm researching the F/IC for tuning the fuel and ignition for my 2001 Suzuki Swift Turbo project. I've read the 6 page thread on O2 Sensors but had one idea that wasn't covered. The standard ECU is dependant on a Narrowband signal for closed loop operation. What I would like to do is throw away the narrowband O2 sensor and put in a wideband for the F/IC or even just a digital gauge, and then send a static "happy stoich" signal always to the ECU.

What I'm wondering, can i just wire the ECU's signal wire for O2 straight from the F/IC? A big part of this would be to not require two O2 sensor bungs pre-cat.

[fantola]

Try to use "fixed" mode of O2 map for generating a signal which is what ECU wants to see.

[varrien]

Yeah that was the plan at the software end. But would I need any special resistors if I'm just wiring the F/IC straight into the factory ECU?

[fantola]

You can wire it without a resistor. However you should notice and set the Hi/Lo voltage.

[varrien]

Yeah I was planning to use the AEM Digital Wideband O2 Gauge to play with the voltages and find stoich then use a fixed map to make the ECU happy, then make my own fuel trims with the MAP Fuel Table. If making a full open loop system ends up being a nightmare, I wont have thrown the narrowband sensor away, and can just add a second exhaust bung for having both sensors.