I'm just curious why I hear people so many people saying that the a/f guages that read the 02 sensor suck? Why?

In open loop the ecu uses it to fine tune it's own maps under light throttle driving. That makes me think there is some benefit to monitoring that signal.

I think also it's a good guage in that it's not so much the exact readings you are looking for, it's the consistancy factor. You'll see if the motor is running crazy lean or something at least 10 seconds before the EGT guage. If you are trying to tune from a WOT then the a/f guage is useless (enter EGT) but in a cruising pace it's a great tool.

I just don't think their as bad and useless as everyone says. Let's hear why they suck. Thanks for your ideas.




[Modified by glagola1, 4:15 AM 7/15/2002]

 

it only reads as accurate as its going to be at WOT, not crusing....it will read in open loop...but yes autometer a/f gauges are junk i believe, greddy makes a nice one...but as long as its green when boosting, i guess then u can say it has a use...then there is also life past fmu and inlines and stock injectors...tuning

 

Yea I just started getting things for my turbo steup, and i put the gauges on as soon as they showed. The A/F isnt consitent at all, only under WOT. As soon as i have the money I'm getting a EGT.
jim

 

actually, the AF is pretty consistent, it's just that the ECM is constantly changing the mix under part throttle, so it jumps all over because the mix is changing. The o2 sensor is pretty damn accurate, but only very close to 14.7:1 ratios, for anything other than fuel economy you need a wideband sensor...I'm not too sure why you need all the other circuitry in the DIY wideband, though.

 

circuits in the controller is to decode the WB o2 sensor. NTK sensor cannot be decoded without a controller.
regular o2 sensor only sense accuratcy near stoich. Example:

regular O2 sense a/f from 0-5 Volt lets say 16:1 a/f to 14:1 a/f. ( just an example, not real numbers)

WB O2 sense a/f from 0-5 volt lets say 20:1 a/f to 10:1 a/f.

So WB o2 see more informations.