Low Res from a Narrow Band - How accurate?

[HopnDude]

Vehicle;
2007 Cobalt SS/SC

Mods;
More than a daily driver needs

I got this config file from either CobaltSS or IonRedline forum board. It works great, an I've had plenty of success in tuning my Cobalt with it (even for a rookie tuner).

QUESTION! There's an "Air Fuel Ratio Command Low Res" that works off the Narrow Band. It seems fairly accurate, I'm just not sure how accurate. I haven't had time to have the car on a dyno just yet with an actual wide band, but I hope that I will soon so that I can see how accurate or inaccurate it actually is.

Here are the config file and the last log I made.

2007 Cobalt SSSC Scanner.cfg / 07 SSSC config log 15.hpl

Thanks for reading! Any helpful information would be greatly appreciated.

[Iam Broke]

Never trust your engine ( or anyone elses) to a narrowband. The're fine around stoich but vary widely off the switching point as when you are in PE.

[GM COBALT SC SS]

you have it backwards. the commanded afr low res is not the data from the narrowband. its the commanded afr. your o2 voltages and fuel trims tell you what the narrowband is seeing for closed loop operation

what broke said as well. dont try to tune pe on the narrowband.

[HopnDude]

Alright, thanks! Guess I'm going to have to order a 2nd AEM EUGO AFR setup.

[noorjSS]

hope this answers your question