Oxygen sensor voltage

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TooTallMike
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Oxygen sensor voltage

Postby TooTallMike » Sat May 05, 2018 11:08 am

Hey guys. Hooked up my reader to check my voltage on my sensors and my b2s1 sensor was reading .9. Ordered another one and hooked it up but there is still no change in voltage.. what gives? Am I just a noob?


TooTallMike
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Postby TooTallMike » Wed May 09, 2018 1:05 pm

So I noticed my car runs better and is more responsive and the dte is way more than I ever got. Typically it was about 265 per tank and then it dropped to 225 and now it's up to 324! Voltage is still high and only drops in range at about 3500 rpm on the highway. I'm stumped as to why it didn't change the voltage but increased range?

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smj999smj
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Postby smj999smj » Wed May 09, 2018 9:04 pm

Your front sensors are air/fuel ratio sensors and work a little differently than a "regular" oxygen sensor, which is what you have in the back. Air/fuel ratio sensors operate in a much narrower range.

TooTallMike
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Postby TooTallMike » Wed May 09, 2018 9:33 pm

So it's okay for bank 1 sensor 1 to be at .4-.5 and bank 2 sensor 1 to stay at .9 ?

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smj999smj
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Postby smj999smj » Thu May 10, 2018 11:40 pm

You would think that would be an issue, but a lot of people have reported similar readings on VQ40DE engines.

TooTallMike
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Postby TooTallMike » Fri May 11, 2018 7:34 am

Hmmmm that is super weird. But milage went up so I'm cool with it! Thanks again !

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underworld1001
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Postby underworld1001 » Wed May 16, 2018 6:49 pm

Wanted to ask about the sensors. Which ones did you get and from where? From what I understand, the upstream ones are the more important ones to replace and generally the most $$$. As I've hit 101000 on my 2011, I'd like to replace them for preventive/general maintenance. If I'm not mistaken there's 4 to replace (2 up / 2 down) on the V6?

TooTallMike
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Joined: Wed Oct 28, 2015 11:32 am
Location: Jblm, Washington

Postby TooTallMike » Thu May 17, 2018 2:56 pm

[quote="underworld1001"]Wanted to ask about the sensors. Which ones did you get and from where? From what I understand, the upstream ones are the more important ones to replace and generally the most $$$. As I've hit 101000 on my 2011, I'd like to replace them for preventive/general maintenance. If I'm not mistaken there's 4 to replace (2 up / 2 down) on the V6?[/quote]

I got the denso one from Rock Auto. The original I pulled was denso also. I'm just confused as to why b2s1 reads .9 almost all the time even after the swap. B1s1 is money at .4 but it did increase mpg.

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disallow
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Postby disallow » Thu May 17, 2018 7:28 pm

My voltage readings are the similarly confusing, as are yours.

I replaced with Denso about 3-4 years ago, and also had an improvement in fuel economy, though it was fairly short lived.

You need to watch the trim readings, and its the speed at which the sensor reacts that is better on a new sensor.

Here is a short video I took of my B1S1 B1S2 B2S1 B2S2 readings.

https://www.youtube.com/watch?v=OX-V8rIE5nM

TooTallMike
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Postby TooTallMike » Fri May 18, 2018 6:28 am

[quote="disallow"]My voltage readings are the similarly confusing, as are yours.

I replaced with Denso about 3-4 years ago, and also had an improvement in fuel economy, though it was fairly short lived.

You need to watch the trim readings, and its the speed at which the sensor reacts that is better on a new sensor.

Here is a short video I took of my B1S1 B1S2 B2S1 B2S2 readings.

https://www.youtube.com/watch?v=OX-V8rIE5nM[/quote]

Yours seem way more responsive than mine. Only when I'm at about 3500 rpm on the highway does my b2s1 sensor come into the normal range. Super confusing because it's constantly at .9


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