SR20 Inside

SR20racer suggested I mess around with the o2 voltage settings on my tt, so last night I held the stick thing to the right and it brought up some values... 10.0 and then 960. I don't know what they mean or if I need to adjust them for the thing doesn't give any instruction on how to adjust it so any help is apprecaited. Thnx.

 

charlie2020

Here we go.......................................dont pat any attention to the theoritical A/F values because they are adjustable and you dont know what a real 10.0, 14.7 or 12.5 A/F really is with a narrow band o2 sensor...................so u need to only concern yourself with o2 voltage which is not adjustable so you cant fu*k it up, its reads directly form the o2 sensor.............so you tune by that........but u gotta learn what values to look for, in short anything but boost should be all over the place, on boost you wanna see voltage's that near 1 volt ex. .96-97v. Laterz

charlie2020

Do a search on o2 voltage with my name there should be a tone of info out there.

SR20 Inside

Alright thanks alot. I've read all your posts about what it should be reading etc... but mine is still f'd up reading around 3 at wot now and .44 at idle so I'll have to try some things to see whats wrong.

charlie2020

What o2 sensor are u using? Did u somehow screw up when extending the o2 wires? What ECU r u using?

SR20RACER

He is using the 300ZX 02 sensor IIRC and he is using the $WT ecu. Charlie, can't you hit the right button on the 02 sensor feature and make some adjustments/setting chages? I could of swore you could, but then again I haven't driven my car in 10 mos so I probably forgot.

charlie2020

U can change the value, but who are you to (now im just talking out loud) to make a o2 voltage of .85v be 12.5 A/F ratio, see what im getting at for instance you can make .70v read 12.5 A/F ratio and your ass will blow up soon.

Unless you know what you are doing dont mess with this feature PERIOD. Like I said only concern yourself with actual o2 voltage.

Obviously not very many people now what i am talking about.

charlie2020

The whole title of this thread is wrong..........o2 voltage is just that it cannot be changed.....................what can be done though is, you can give a particular real life o2 voltage a fake value (theorictal value) for instance, im not even gonna go there because it shouldn't be done, i could get into it further but why, first learn how to crawl before u try and walk, there is plenty info out on the net for you to get a general understanding of what semi-relationship o2 voltage has to "actual" wide band air fuel ratio's.

SR20RACER

Charlie, his 02 voltage on his TT displays like 3.XX and around there, I remember when I had mine running and tuning with your help and remember seeing .90-.98 voltages.

What he is trying to see is if he has the TT set-up wrong, I know there is some setting inside the TT itself and we were trying to figure out if those need to be changed to get the right 02 voltage (.90) to display versus the 3.XX we are seeing now.

SR20 Inside

Yea charlie its weird and the thing is that my techtom seems to be reading more correct values.. at warmup the voltage is .33 and then wot its like .92 or whatever just like you said but its all over the fu*king place.. i can just see it hit those numbers. For some reason my tt is reading wrong... maybe spliced the o2 wire into the wrong one on the ecu? but that wouldnt make alot of sense seeing how i was getting10 readings prior to sealing up all my exhaust leaks.

charlie2020

OK for one you cannot change o2 voltage, so in other words somewhere a wire is crossed or somesh*t or he is using a Titania (BlueBird U12 o2) the skinny abnormal looking one. No Zirconia o2 reads in the 1v - 5v scale.

If your are in fact in the o2 voltage window of the TT and your getting voltages in the 3.xx range and your using the stock o2 sensor there is a problem or there is an error u made.

and for the last time you can not change o2 voltage on the TT you can only change Theoritical A/F ratio, so o2 voltage is what it is, and cannot be changed to read to your liking thank god, else alot of people could be in trouble. Obviously u haven;t grasped enough info yet to tune by o2 voltage, my friend read read and read somemore before u fu*k something up cuzz u dont know what ur doing, dont take this lightly.

SR20 Inside

lol im not giogn to change any of the values but do you know the part of the tt that i am talking about where you can hold it sideways while looking at o2 voltage and itll bring up ways to change the scale or some sh*t that it's displayed in... something like that. Maybe I did just splice in th ewrong wire, never really knew exactly which one to do it on.

NismoSER

I'm having issues right now with my turbo timer. For some reason it reads 0.01 volts almost all the time. Sometimes it will go up to 0.08 under WOT, but that's about it. I'm going to redo my wiring (I extended the engine harness for the connector to be closer to the DET's o2 bung).

I checked and redid the wiring from the TT to the ECU, and that's fine.

As an aside...anyone have an extra Avenir T25 wastegate actuator laying around? (i've been without boost for a month... )

__________________
Chris
'91 VVL-powered SE-RSOLD
VE! Koni/GC's, Apexi, Progress, Crown, Carbotech, ACT, GSpec, Fidanza, VDO, Nismo, and other goodies
'04 G35 6MT
'99 CBR600 F4

charlie2020

ITS POSSIBLE YOUR o2 SENSORS ARE BAD, DO THE O2 SENSOR TEST

NismoSER

Yea, I'll be doin the o2 diagnostic test later tonight when I get home. I suppose it could have gone bad, but this one is less than 2 months old....

I'll post back tomorrow with results.

charlie2020

Do the multimeter test with propane torch better

SR20 Inside

I finally was able to tap into the o2 wire... i had it in the tps wire before. And I have the exact same problem.. it has to do something with the settings for the a/f values to read off the o2 voltage on the tt. I am still trying to figure it out for myself. Check out these settings and let me know what you think.

SR20 Inside

how does that work?
you don't happen to know what values we need to adjust the tt to for that o2 voltage?

SR20 Inside

I don't understand your concept about a theoretical value for an o2 voltage. Obviously it does have a correct real life value. You are saying that you can't assign a value to the o2 voltage on the turbo timer but that makes no sense because the tt has to read o2 voltage compared to the a/f ratios regardless. How is it supposed to know the correct o2 voltage for an sr20 when it is made for so many different cars? You have to assign it some false value that corresponds correctly with the voltage of the o2 sensor so you get some idea of rich or lean or it won't work. So I'd appreciate it if you'd explain yourself a little more because it seems that you can assign whatever value you want to the tt for the o2 voltage etc.... so there has to be some value that is somewhat correct....

charlie2020

I dont feel like it......honestly most people just dont understand what im talking about, the closet way you could get the theoritcal A/F value to work would be to datalog the real time o2 voltage to a wide band A/F ratio then adjust the Apex TT theoritcal A/F value to match accordingly but even then the o2 voltage is still gonna change as the o2 sensor get hotter and cooler and this will in turn change values, thats all im gonna say.