Tonyrodz's Tahoe Build Thread

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kbuskill

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The upstream O2 sensors MV should bounce back and forth constantly between 1xx MV and 9xx MV if they are reading properly because they are constantly adjusting the fuel trims.

He probably just snapped the pic when it was making it swing to the lower end of the spectrum.

Sometimes you can watch them and see if one is "lazy" where it isn't bouncing around as much or kind of lags.
 
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Tonyrodz

Tonyrodz

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The upstream O2 sensors MV should bounce back and forth constantly between 1xx MV and 9xx MV if they are reading properly because they are constantly adjusting the fuel trims.

He probably just snapped the pic when it was making it swing to the lower end of the spectrum.

Sometimes you can watch them and see if one is "lazy" where it isn't bouncing around as much or kind of lags.
If it was an easy deal to swap the o2s I'd do it asap, but I'm still jaded from the ordeal with the Tahoe. That was a cluster in itself--and that was just replacing 1!
 
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Tonyrodz

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Just look at live data and see if they’re all operating right.
I'll give it a shot. Is it under "Special Functions"? Still feeling my way around the tech2. Should the numbers be fairly close to each other? Up and down stream? Thx.
 

kbuskill

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I'll give it a shot. Is it under "Special Functions"? Still feeling my way around the tech2. Should the numbers be fairly close to each other? Up and down stream? Thx.

Should be under data display or live data or something like that.

Both upstream sensors should fluctuate back and forth fairly rapidly. They could be similar, as far as MV is concerned, but they definitely won't match.

And No, the upstream sensors will not match the down stream sensors.

The downstream sensors only purpose is to monitor the catalytic converter's efficiency. They have ZERO effect on fuel trims.

You can basically ignore the downstream O2 sensors data in this case.
 

Rocket Man

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I'll give it a shot. Is it under "Special Functions"? Still feeling my way around the tech2. Should the numbers be fairly close to each other? Up and down stream? Thx.
I never remember where anything is in the Tech2 menus, I just look around every time until I either find what I’m looking for or decide it doesn’t exist. :yaoface2:
 

Scottydoggs

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if reading just the o2 voltage it should bounce up and down all the time. if scanning in (Mv) wot they should both hit 930 ish and lock there till you let off. normal driving and idle they will be any where from 300 up or down. both will never read 100% the same.

when wot if one dont hit high 800's or lock there, or it drops at all, that o2 s bad.

in voltage if its real slow to move up and down, once again, its gotten lazy.

it really funny to me how a lazy o2 wont set a code. had it happen a few times over the years.
 
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