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#o2 sensor installation, i guess mine is wrong

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 Post subject: o2 sensor installation, i guess mine is wrong
PostPosted: Fri May 20, 2016 2:17 am 
In Neutral
Joined: Tue Jul 22, 2008 6:27 pm
Posts: 37
Hi!

i have read that on this model there is not a really an appreciable difference in gas mileage, i know it is for keeping the gases wihtin the manufacturer range... but usually it improves the fuel mileage since without it (the o2 sensor) the system by default would set to a rich mixture...

after installed the new o2 sensor, the check engine light went off and the mileage increased by 0.6 or 1mpg (several method to measure)

but i wonder

please, check the image
Image

i know the sensor should be installed like the no. 1 example
BUT mine (after relocated, because this vehicle had catalitic removed)
the muffler guy installed like the no. 2, he told me that the o2 sensor does not need to be in "full" contact with the gases, that only needs a "little" doze of the gases in order to make its job....
not too satisfied with this, i wanted to ask you if i should go back to the muffler shop and make him to desolder the o2 sensor socket again and to make him to solder at its correct level so the part of the o2 sensor that must be exposed to the gases is fully exposed?

just like the no.1?


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 Post subject: Re: o2 sensor installation, i guess mine is wrong
PostPosted: Thu Jun 23, 2016 5:44 pm 
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Joined: Tue Oct 15, 2002 11:37 am
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Location: Houston, Tx
Do you know how much of the O2 sensor is sticking out into exhaust stream?

Any pictures you can share?

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surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
1997 Impreza OBS

If you need to get a hold of me please email me rather then pm


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 Post subject: Re: o2 sensor installation, i guess mine is wrong
PostPosted: Sun Jul 03, 2016 6:34 pm 
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Joined: Tue Jul 22, 2008 6:27 pm
Posts: 37
hi!

you mean, how much of the sensor is immerse into the exhaust tube?


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 Post subject: Re: o2 sensor installation, i guess mine is wrong
PostPosted: Sun Jul 03, 2016 9:16 pm 
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Location: Des Moines, Wa
Im not convinced that the old ecu and o2 sensor setup is smart enough to tell a difference. On a newer car with a bad cat, you cheated and fooled the ecu by pulling the o2 sensor further out of the exhaust stream, like example 2. Your car was still polluting more than normal, but the ecu doesn't know that, and doesn't put you into limp mode (or simply trigger a CEL). Like I said, I dont believe our cars are anywhere near sophisticated enough for that to make a difference.

Your best bet would be to install a wideband sensor and gauge into a bung a welder installs on your exhaust. Then you could see what the engine is actually doing.

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 Post subject: Re: o2 sensor installation, i guess mine is wrong
PostPosted: Mon Jul 04, 2016 6:30 am 
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Joined: Tue Jul 22, 2008 6:27 pm
Posts: 37
i understand your point, althought i am not clear with the last part (most due my english limitation :( )
BUT i dont know, to relocate the sensor in order is deeper into the gases cost me about us15.

i knowour ECU is not smart enough, but its a simple parameter, maybe the voltage is receiving from the sensor is not bad enough to trigger the check engine light, BUT if it has a sensor is because even a rudimentary maybe 5 points of preset levels should has, i mean, not weak enough to trigger the light but in the lower range of (assuming the most rudimentary and basic scale/sensing/resolution) a 3 presets settings where:

situation cause ecu response
1-high o2 lean mix enrich
2-right amount normal none
3-low o2 rich mix lean the mixture

using a rudimentary and not full of data logic

if the engine is in order (all sensor hoses filter, everything is tune up), if the sensor is less than normal exposed to the gases, in a normal combustion it would receive less gasses to generate the right amount of voltage... right? then the ecu would sense that there is a low content of 02, leaning the mixture and then the vehicle will consume more fuel because the engine is running lean, it is weak and need more revs to move the same mass
(i have a small euro car, it came with a 1.1liter engine and i swap its engine to a 1.4liters with almost double the HP and the mileage went from 37.5mpg to 48.75mpg just with the engine swap, the previous 1.1L engine was too weak, i needed t rev it more to get i moving)

i mean its a theory

what you think?

i mean this is asuming our ECU is not smart enough to get precise chanegs from information recivied form the o2sensor but since it is a sensor and not a switch it has at least or more than those three sets i mentiones otherwise would be only, on/off, or rich/lean, or there are oxygen, there arent.. i think you got my point lol


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 Post subject: Re: o2 sensor installation, i guess mine is wrong
PostPosted: Mon Jul 04, 2016 8:39 pm 
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Location: Houston, Tx
Honestly, if you have a concern with it and if I was in your shoes I would just pay the extra $15 for peace of mind.

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Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
1997 Impreza OBS

If you need to get a hold of me please email me rather then pm


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 Post subject: Re: o2 sensor installation, i guess mine is wrong
PostPosted: Wed Jul 06, 2016 8:03 pm 
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Joined: Mon Aug 31, 2009 9:09 pm
Posts: 1204
Location: Rochester, WA
It is fine as-is. Being out of the exhaust stream will not cause it to read improperly, the small space simply dampens quick changes in oxygen content.

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2005 Legacy GT Limited Wagon 5-Speed. Stock-ish ;)


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