o2 sensor voltage
02-13-2008, 01:44 AM
#1
10 Second Club
Thread Starter
iTrader: (38)
Join Date: Oct 2006
Location: Phoenix, Az
Posts: 1,259
Likes: 0
Received 0 Likes
on
0 Posts
o2 sensor voltage I am looking for a chart that has your o2 sensor voltage converted to an actual AFR. I am wanting the chart for the factory narrow band sensor. Can someone please post up a link. Tried searching no luck. Thanks!
02-13-2008, 05:43 AM
#2
TECH Regular
The answer you are going to get is there is no such chart.
I spent 12 hours logging data. Ploting charts. And for my car and my o2's I could get to within about .5 AFR at a given o2 reading. But I believe that you can get widely differant readings from differant o2's.
The only way to test it is too have a WB, and a tool to read the OEM o2 and log both at the same time to compare. and access to 10 cars to cross compare differant OEM o2's. I really doubt it has ever been done.
But, all you are going to find is guys that are trying to prove it will NOT work. It is easy to do that. It isn't so easy to actually try to prove that it will to some degree.
I have posted some of the data and charts that I came up with. I'll try to find a link to it.
This is not the one I wanted but.....
https://ls1tech.com/forums/showthrea...709&highlight=
ah, here it is:
http://www.ls1gto.com/forums/showthread.php?t=193871
Over 200 posts, graphs, scatter charts. If you don't want to read it all scan for the posts with charts.
I spent 12 hours logging data. Ploting charts. And for my car and my o2's I could get to within about .5 AFR at a given o2 reading. But I believe that you can get widely differant readings from differant o2's.
The only way to test it is too have a WB, and a tool to read the OEM o2 and log both at the same time to compare. and access to 10 cars to cross compare differant OEM o2's. I really doubt it has ever been done.
But, all you are going to find is guys that are trying to prove it will NOT work. It is easy to do that. It isn't so easy to actually try to prove that it will to some degree.
I have posted some of the data and charts that I came up with. I'll try to find a link to it.
This is not the one I wanted but.....
https://ls1tech.com/forums/showthrea...709&highlight=
ah, here it is:
http://www.ls1gto.com/forums/showthread.php?t=193871
Over 200 posts, graphs, scatter charts. If you don't want to read it all scan for the posts with charts.
Last edited by ericwilloughby; 02-13-2008 at 05:57 AM.
02-13-2008, 08:08 PM
#3
10 Second Club
Thread Starter
iTrader: (38)
Join Date: Oct 2006
Location: Phoenix, Az
Posts: 1,259
Likes: 0
Received 0 Likes
on
0 Posts
Thanks for your help! I've got a Innovate LM1 wideband setup that I'll usually switch between cars. I just got my Scanmaster back and on its main screen it displays the current o2 voltage. It will also log the o2 reading @ WOT. More than anything I was just wondering what the correlation between the actual AFR and voltages are.
02-13-2008, 10:09 PM
#4
Moderator
iTrader: (11)
Join Date: Mar 2002
Location: East Central Florida
Posts: 12,605
Likes: 0
Received 6 Likes
on
6 Posts
It's very poor because exhaust gas temperature moves the
output more than AFR does, in the enrichment range you
care about. First two charts illustrate that.
The third pic here is data off my car, you can see maybe 75
to 100mV of scatter in the narrowband output at 13:1 AFR,
and almost no slope. So good luck pinning any given voltage
value to a specific AFR. And this is with nice hot manifolds,
with headers your temperature variation is much greater.
output more than AFR does, in the enrichment range you
care about. First two charts illustrate that.
The third pic here is data off my car, you can see maybe 75
to 100mV of scatter in the narrowband output at 13:1 AFR,
and almost no slope. So good luck pinning any given voltage
value to a specific AFR. And this is with nice hot manifolds,
with headers your temperature variation is much greater.
02-14-2008, 06:37 AM
#5
TECH Regular
This is what I am talking about. The charts other guys will post are over such a wide range of AFR, o2 v and other crap like load and tp that they really are useless to pull data from. And almost no one will actually post the log the data is from.
The charts in that ls1gto thread of mine include actual logs and the excel data points that the charts are made from. It takes a GREAT deal of time to go into a log and eliminate all data that is not relevant: I.E. other than WOT, tip in, I got big errors on the top end until I realized that just before the rev limiter the ECM leans the mix by 1 AFR but that does not show up on the commanded AFR.
You are the man to do this research, you have a wb and nb. Make a short log or 2 of WOT pull and send it to me. I've gotten good at extrapolating the relevant data and making charts that only include .85 to .99 vs. at WOT.
The charts in that ls1gto thread of mine include actual logs and the excel data points that the charts are made from. It takes a GREAT deal of time to go into a log and eliminate all data that is not relevant: I.E. other than WOT, tip in, I got big errors on the top end until I realized that just before the rev limiter the ECM leans the mix by 1 AFR but that does not show up on the commanded AFR.
You are the man to do this research, you have a wb and nb. Make a short log or 2 of WOT pull and send it to me. I've gotten good at extrapolating the relevant data and making charts that only include .85 to .99 vs. at WOT.
02-14-2008, 06:40 AM
#6
TECH Regular
Oh, and I saw no change in the readings that I thought were do to temp. The only inconsistencies I saw in my data I attributed to the load. All pulls in 2nd gear were the same but a little richer than all pulls done in 3rd gear.
