O2 Sensors

TeknoMage

Member
Feb 19, 2003
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From what I understand, we have powered O2 sensors.

Dose anyone know what the input power is?
And dose anyone know what the output range is and corresponding air/fuel ratio?

I'm looking for as much technical info as possible.

Thanks guys.
 
I don't have the info for you but I am wondering if you want to try to figure out if yours are bad, or if your trying to make your own MIL eliminators? in that spirits I'd like to ask how you know if your MILs are bad when testing on a multimeter. :P
 
Mine are fine... except for the one I melted on my L/Ts. :D

I already know how to make MIL eliminators. (just takes a couple bucks at radio shack)

I plan to use this info for another idea I have :rolleyes:
 
Input (I beleive) is 12v output is between 0 and 1 volt. I can give you some values of my drivers side front o2 and how they relate to my a/f read with my wideband.

o2 voltage -------A/F
0.98828125--------10.5078125
0.154296875-------11.09375
0.19140625--------11.5234375
0.947265625-------12.03125
0.4765625---------12.5
0.120117188-------13.0078125
0.9296875---------13.515625
0.87890625--------14.0234375
0.481445313-------14.53125
0.475585938-------15.078125
0.361328125-------16.0546875


As you can see the voltage can really vary.
 
Amperage isn't really important w/ O2's. Like its been stated the range is roughly 0-1v. I'm pretty sure we have zirconia O2's which produce a voltage, not modify it like titania O2 sensors. But if you want, you can use a T-pin and backprobe them with a meter. That should give you an idea whats going on. Id recommend using a scope but most people dont have access to one. The voltage will always be a DC signal going up and down. That is the sensor reading gas pulses entering the exhaust everytime the engine fires. So it is constantly going from rich to lean. If you look at the pattern on a scope it will be a wave. O2s produce very little voltage. You'd have to look up the specs for the voltage ranges. I belive over .5v is rich, under is lean, and .5v is stoichiometric (14.7:1)
 
SLOW 97 said:
Amperage isn't really important w/ O2's. Like its been stated the range is roughly 0-1v. I'm pretty sure we have zirconia O2's which produce a voltage, not modify it like titania O2 sensors. But if you want, you can use a T-pin and backprobe them with a meter. That should give you an idea whats going on. Id recommend using a scope but most people dont have access to one. The voltage will always be a DC signal going up and down. That is the sensor reading gas pulses entering the exhaust everytime the engine fires. So it is constantly going from rich to lean. If you look at the pattern on a scope it will be a wave. O2s produce very little voltage. You'd have to look up the specs for the voltage ranges. I belive over .5v is rich, under is lean, and .5v is stoichiometric (14.7:1)

you're right on target with that except that when you're looking at the voltage on the scope, you use .450v as your center line and want to see it go over and below the center like 1 every 10 ms. constanly Over .450v is rich and constantly under is lean. If the pulse is slow or doesn't pulse as high or low as it should then you know the sensor is bad is bad. (we're only talking about the front sensor here.) you never want to see the voltage stay constant or in lean or rich zone. it should switch back and forth. the second o2 is is only for measuring the 1st sensor's performance. if the back sensor ever starts to mimic the front o2 then you know it's bad. stoichiometric (14.7:1) is perfect air / fuel combustion at sea level

By the way, good job JS!
 
Here is a graph I put together that compares the same data in more detail. The o2 voltage is pulled from the drivers side front o2 and the A/F is logged from my PLX wideband in the drivers side rear o2 bung.
attachment.php
 
jstreet0204 said:
Here is a graph I put together that compares the same data in more detail. The o2 voltage is pulled from the drivers side front o2 and the A/F is logged from my PLX wideband in the drivers side rear o2 bung.
attachment.php

is that the o2 graph from your car? that's cool.

by the way what happened that you found out that your autologic chip went bad?? Was it a 1 position or 4 position chip? I haven't heard of anyone having a bad chip. Can you give me some details. I'm really curious about it thanks.
 
lwkauble said:
is that the o2 graph from your car? that's cool.

by the way what happened that you found out that your autologic chip went bad?? Was it a 1 position or 4 position chip? I haven't heard of anyone having a bad chip. Can you give me some details. I'm really curious about it thanks.

Yeah its from my car. I use the tweecer and a dataq to do the dataloging the export it to an excel file. The chip didn't go bad until I went to have it reburned, ad it had a bad data sector so you could no longer write to it or read from it.
 
jstreet0204 said:
Yeah its from my car. I use the tweecer and a dataq to do the dataloging the export it to an excel file. The chip didn't go bad until I went to have it reburned, ad it had a bad data sector so you could no longer write to it or read from it.

wow, trippy! Was it only the second time it had been reburned that you found out?? or was it a few times.