and hook it up for use through the ECU?

just a thought, i did search but was not able to come up with anything usable.
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if your wideband has a narrowband output, yes you can.
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If the WBO2 controller has narrowband output then you could pop out the front sensor and use the wideband in place of it.

If you unhook the rear O2 you will get a check engine light for CAT efficiency.

I really wouldn't put an O2 sensor post cat anyway. You won't get accurate reading. Ive heard of dyno shops shoving a wideband up the exhuast pipe but they won't get as accurate of a reading as a pre-cat WBO2.

Brad
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well the car has no cats,

so is it a connection problem or the WB wont give the right info to the ECU?:confused:
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well the car has no cats,

so is it a connection problem or the WB wont give the right info to the ECU?:confused:

If you're car has no cats, you don't need to worry about anything; your WBO2 will work fine in the rear O2 sensor spot. You'll need WB -> narrow-band output, so your ECU stays happy (or a reflash to eliminate any CELs).

Lastly, you'll have to figure out what you want to do about the heater circuit CELs you'll get when you pull the stock O2 sensor. Possible options are: running a resistor or using a reflash.
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If the WBO2 controller has narrowband output then you could pop out the front sensor and use the wideband in place of it.

If you unhook the rear O2 you will get a check engine light for CAT efficiency.

I really wouldn't put an O2 sensor post cat anyway. You won't get accurate reading. Ive heard of dyno shops shoving a wideband up the exhuast pipe but they won't get as accurate of a reading as a pre-cat WBO2.

Brad
Considering that the OP has a '04 WRX, this is incorrect. The factory front O2 sensor is not a narrowband sensor. Plus, an aftermarket wideband will not function properly in the high-pressure pre-turbo exhaust. I would just put the wideband in the rear location, and reflash the CELs away.

Cats have been shown to have negligible effect on AFR readings, but most performance-minded WRX owners will be catless anyway.
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ok lol, mabe i should have listed my mods

vf34 p&p
txs top mount
pullies
sti pinks
walbro
full TBE
catless

front 02 is in place

i was protuned
now i am tuned with enginuity, so the whole CEL thing is taken care of.

so if i am understanding this right.

i can use a WB02 in the rear bung(midpipe area not in the DP)
i can use the existing wires and use the ECU to read the sensor

using ecu explorer or the enginuity software to log the information being sent to the ECU from the WB02. it should translate just fine, right?

cause right now the rear 02 is gone for all intent and purpose.

so i figure i can replace it with something that will do some good.

let me know if i am on the right track or way st00pid
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i can use a WB02 in the rear bung(midpipe area not in the DP)
Yes.

i can use the existing wires and use the ECU to read the sensor
Nope. From what I recall, the ECU doesn't report an AFR from the rear sensor.

Your best bet is to use a WB sensor/controller that is supported by your logging software (e.g. Innovate LC-1 or LM-1).
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i thought it did.. it would be nice
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it reports a voltage. but the voltage can be translated to an A/F or lambda whichever you prefer using for tuning.
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so it should work?
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quick bump for the nite crew
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one last time for the giggles of it
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so it should work?

Nope. At least not on any widebands I'm aware of. Wideband O2 uses a control current to determine AFR, not a raw voltage output. Sock rear O2 reads an output voltage (0-1V) so if you strap in, say, a Bosch WBO2, the stock ECU won't read it. You MAY be able to use an aftermarket WB controller with a separate analog output that's proportional to AFR (I know ECM makes a couple) Then plug the analog output into the stock ECU, but you're still stuck with the fact that the stock ECU reads 0-1V (I believe) and most analog outputs from WB controllers are 0-5V, so NFG.

Best bet would be to either move your front O2 to the rear location (possible idle issues, but you'll get a much more accurate AFR reading without the backpressure) OR use an aftermarket AFR system.
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The LM-1 and LC-1 have a fully programmable output (can be set to 0-1V), but why bother?

Datalog an Innovate wideband directly into your logging software (DeltaDash, ecuExplorer, etc.) and call it a day.
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Not to hijack but I am somewhat interested in this same thing. The twin scroll turbo setup has no oxygen sensor in the manifold. The front oxygen is in the downpipe right after the turbo. I know there is a difference between narrow and wide.

I have and innovate lc-1 kit and would like to just use the single location right after the turbo for a wideband readout to my street tuner software but also have it function as the ECU's narrow sensor. It seems possible but I am unsure at this point.
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On the USDM WRX/STi, the ECU doesn't get it's AFR from the front O2 via voltage... that's why you can't replace it with an aftermarket wideband with a voltage output. I doubt that the JDM models are much different.

The short answer: Just weld another bung in the downpipe. Innovate widebands don't like to be too close to the turbo anyway.
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sry to thread jack but would i still get an accurate afr reading on a wideband from the rear o2 sensor position? I had a friend weld in a bung, but he put it in the wrong spot so i have no clearance. i would rather just put it in the rear bung!
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