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Discussion Starter · #1 · (Edited)
3.0 V6 GTS 2003

I had my CEL come on, and it read Bank 1 Sensor 2 filament failure.

I understand that means the heater filament on that o2 sensor has gone bad..

And I also THINK i understand the Bank 1 indicates the side cylinder 1 is on, being facing the rear of the car...

And Sensor 2... is the second one inline?

Autozone lists 2 different parts for this, can someone point me to the correct part?

Universal or OEM I dont care either way.

thanks in advance for any help
 

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2011's are gay
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it is the sensor after the pre cat on the rear, and oem or universal doesn't matter, you just have to solder the universal one to your existing plug, just make sure to keep the wire the same length as before
 

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Discussion Starter · #3 · (Edited)
it is the sensor after the pre cat on the rear, and oem or universal doesn't matter, you just have to solder the universal one to your existing plug, just make sure to keep the wire the same length as before
Is that going to be upstream or down stream? I know after the cat is "downstream" but this is after the precat, so I am assuming its upstream?

They have 4 different o2 sensors listed and the guys at the local car parts stores have no freakin clue. I keep getting mixed information.
 

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Resident Asshole
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Precats are cats. You have one in front and one behind. Hence upstream and downstream.
 

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Waiting to spool
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Any "sensor 2" is a downstream on the 3g. (on the v6 atleast)

Sensor 1 is all upstream. The bank (as you know) is just which manifold it starts on.
 

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Senior Dangler
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The two cats that are bolted to the manifold are oxidation beds. The upstream o2 sensor is located in the manifold, and it reads A/F based on the oxygen level present in the exhaust. The oxidation bed (pre-cat) then oxidizes, and removes all but around .2 percent of the o2 in the exhaust. The downstream is the sensor 2 on each bank. It is located after the cat and measures the change the cat causes.

That bottom cat is techincally just a reduction bed.
 

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fat guy tiny car
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this is by far the most god damn difficult thing i've tried to replace on this car so far. even with the sensor socket and some pb blaster this thing will not budge.
 

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Boobs!? WHERE!?!
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Fashion yourself a breaker bar and pray like Hell. It WILL come out... just gotta "finesse" it a bit all while using copious amounts of PB.
 

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fat guy tiny car
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gave this another shot today and i've officially stripped the sensor. i have 2 different sensor sockets and both slip right off. pb blaster you can go to hell. guess ill just buy headers and say screw getting this one sensor out
 

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You may want to start your vehicle for a bit because when the catalytic converter or exhaust manifold cools, they contract. The oxygen sensor may be very difficult to loosen when the engine is cold. Rather than risk damage to ther sensor, start and run the engine for a minute or two and then shut if off and proceed with caution and try not to burn yourself.
 

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fat guy tiny car
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848 Posts
You may want to start your vehicle for a bit because when the catalytic converter or exhaust manifold cools, they contract. The oxygen sensor may be very difficult to loosen when the engine is cold. Rather than risk damage to ther sensor, start and run the engine for a minute or two and then shut if off and proceed with caution and try not to burn yourself.
its stripped, socket sensor is useless. there's not enough room down there to get a vise grip or any other wrench for that matter. i'd tried to remove the entire pipe so i could work on it outside of the engine bay, and ended up pulling a bolt out of the part above the cat, and one of those bolts underneath the cat snapped on me. this entire exhaust seems to have seized.
 

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I have CEL of PO141 and I just wanted to make sure I replace the right sensor so i took some pics.






I can't figure out which bottom one I need to replace. Help out alot if someone can tell me which one.
 

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R.I.P. silverside
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Nope, that's Bank 2 Sensor 2. Keep going further back, it's near the axle boot.
 

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R.I.P. silverside
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I have CEL of PO141 and I just wanted to make sure I replace the right sensor so i took some pics.

Nope, that's Bank 2 Sensor 2. Keep going further back, it's near the axle boot.
For your clarification this is the pic I was referring to when I replied with my last post. Again, this is Bank 2 Sensor 2. Like I said keep going further back, it's near the axle boot.
 

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R.I.P. silverside
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That's one horrible picture, but yeah that's it.
 

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fat guy tiny car
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lol all that was taken care of a few weeks ago, buddy. removed the entire exhaust and installed some headers. was able to get 3 of the o2 sensors out but that stripped one is still stuck in there. i did have to use a torch for the 3 that i got out, though. and i don't really need to get that last one out now anyhow. but what i dont get is, i pulled 4 sensors from 3 different eclipses at the junkyard, and they all came out with about a quarter of the effort of getting even the easiest of mine out. weird :dunno:
 
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