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bOOOOstedAudi
06-27-2007, 11:00 AM
Can you tap into the o2 sensor to get the proper reading. what color wires should I be looking in to.

pinky
06-27-2007, 11:07 AM
wideband (actual a/f number) or narrowband (lean/rich)??

bOOOOstedAudi
06-27-2007, 11:21 AM
its the apexi one. i beleive wide band. http://www.jazzproparts.com/photos/401-A011-2.jpg

maxspeed
06-27-2007, 01:04 PM
you have an 01 correct?

Ewok_Fetus
06-27-2007, 02:37 PM
I have always been told even if you are an 01, to get a seperate o2 for this...

bOOOOstedAudi
06-27-2007, 04:40 PM
No I Have 2000

mike-2ptzero
06-27-2007, 06:49 PM
I have always been told even if you are an 01, to get a seperate o2 for this...

Correct. You can not splice into a wide band 02 sensor harness like you can a narrow band 02 sensor.

bOOOOstedAudi
06-27-2007, 07:34 PM
why not. thats gay

Ewok_Fetus
06-28-2007, 03:11 AM
I would like to know why not as well... Afterall, an AFR gauge is nothing more than a voltmeter... Sensor puts out voltage, gauge reads it... What more need there be?

98a4
06-28-2007, 05:35 AM
Paracitic drain if I had to guess, pulling 2 sorces for reading off of one low voltage...

Wideband FTW

By the time your narrowband tells you theres a problem, you motor has already blown up.

mike-2ptzero
06-28-2007, 06:33 AM
I would like to know why not as well... Afterall, an AFR gauge is nothing more than a voltmeter... Sensor puts out voltage, gauge reads it... What more need there be?

A narrow and wide band 02 sensor work in completely different ways. It isn't just that one reads in 0-1 volt vs 0-5 volt. Just look at how wide band systems are sold. There is always something that must be plugged in between the sensor and gauge.

Boooosted, it really doesn't matter for you since you dont have a 5 wire(wide band 02) in your car since you own a 2000.

_audible_
06-28-2007, 07:22 AM
Ok so I have a couple of small questions. Searching didn't yield a clear answer. I have a '00 B5 and I just picked up an AEM UEGO A/F controller. Now, since my car uses a narrow band O2 sensor, do I simply leave the narrow band in place and weld a new bung for the wideband O2 sensor? Also, how far below the cat should the wideband O2 be mounted? I'm guessing that's all that needs to be done since the ecu will still read the narrow band and the gauge will be reading the wideband. Correct?

creechsa4
06-28-2007, 09:47 AM
boosted, the apexi is a narrowband, i have the same one. it's the black wire that i tapped into

Ewok_Fetus
06-28-2007, 01:26 PM
A narrow and wide band 02 sensor work in completely different ways. It isn't just that one reads in 0-1 volt vs 0-5 volt. Just look at how wide band systems are sold. There is always something that must be plugged in between the sensor and gauge.

Boooosted, it really doesn't matter for you since you dont have a 5 wire(wide band 02) in your car since you own a 2000.

Correct me if I am wrong, but... I have always been told that for a "volt meter" it doesn't interfere with the readings at all... I am also talking volt meters here and not AFR gauges... But the volt meters have a very high resistance internally so it will not cause paracitic drain... Also, from the schematics I have been studying up on to make my OWN wideband controller, that is more for controlling the heater circuit of the wideband since they need to be a specific tempurature to work, unlike narrowbands... Though I have seen some gauges that need a specific controller since the signal sent from the o2 to the controller converts it into something the gauge can read... But if you get a gauge with the a/d converter already built in, there should be no problem...

Not trying to start an argument here, just learning a bit... As for the wideband controller, an Engineer for Northrop Grumman is helping me build it...

k0mpresd
06-28-2007, 07:51 PM
Correct me if I am wrong, but... I have always been told that for a "volt meter" it doesn't interfere with the readings at all... I am also talking volt meters here and not AFR gauges... But the volt meters have a very high resistance internally so it will not cause paracitic drain... Also, from the schematics I have been studying up on to make my OWN wideband controller, that is more for controlling the heater circuit of the wideband since they need to be a specific tempurature to work, unlike narrowbands... Though I have seen some gauges that need a specific controller since the signal sent from the o2 to the controller converts it into something the gauge can read... But if you get a gauge with the a/d converter already built in, there should be no problem...

Not trying to start an argument here, just learning a bit... As for the wideband controller, an Engineer for Northrop Grumman is helping me build it...
quit running your mouth ;)

read ~> http://www.forparts.com/BoswidebandO2.htm

and plus..youre not going to win an arguement w/ mike anyways.. ;) :p

k0mpresd
06-28-2007, 08:00 PM
Ok so I have a couple of small questions. Searching didn't yield a clear answer. I have a '00 B5 and I just picked up an AEM UEGO A/F controller. Now, since my car uses a narrow band O2 sensor, do I simply leave the narrow band in place and weld a new bung for the wideband O2 sensor? Also, how far below the cat should the wideband O2 be mounted? I'm guessing that's all that needs to be done since the ecu will still read the narrow band and the gauge will be reading the wideband. Correct?
for the best installation then yes, leave the stock o2 and weld a 2nd bung in

wideband should be before the cat..so both ecu and wideband receive the same reading

mike-2ptzero
06-28-2007, 08:33 PM
for the best installation then yes, leave the stock o2 and weld a 2nd bung in

wideband should be before the cat..so both ecu and wideband receive the same reading

Actually the correct spot for a wide band is more down stream which would be after the cat near the bottom of the down pipe. If you put it too close to the engine you will get false lean spikes when the car misfires even though at that point the car is actually running very rich. Believe me I had this problem when my wide band 02 sensor was mounted right next to the first OEM 02 sensor which was right behind the turbo.

k0mpresd
06-28-2007, 08:42 PM
my wideband is right after the turbocharger..never had an issue

lots of ppl say further down the downpipe but i would not want to tune on post cat o2 readings..and i think a lot of those ppl assume catless

if the car is misfiring then you need to work on that issue instead of what your wideband says while the car is misfiring

but i already said no one is winning an arguement w/ you ;) :p

b5gen
06-28-2007, 09:00 PM
well i have a 97 b5 a4 qtm and i just recently installed my autometer cobalt a/f gauge and I was wondering do I tap into the grey,black,or any of the two white o2 wires? i kno this is threat butting but i dont feel like starting a new thread.

mike-2ptzero
06-28-2007, 09:30 PM
well i have a 97 b5 a4 qtm and i just recently installed my autometer cobalt a/f gauge and I was wondering do I tap into the grey,black,or any of the two white o2 wires? i kno this is threat butting but i dont feel like starting a new thread.

Black wire. Then get ready for the "disco ball" effect to begin.

_audible_
06-29-2007, 05:49 AM
Lol at the disco ball. Throw some techno in and you've got yourself a little in-car rave action. Thanks for the info. I've read downstream was the ideal spot as well, but I was wondering if there's an actual "sweet spot" of sorts for it? Also, how can it be mounted before the cat? Onto the exhaust mani?? Post cat tuning does seem like a relative issue to look at when using one of these. It does make sense that your readings may be altered being mounted after the cat, but to what degree? Mike? Kompressed? Any thoughts since you both have yours mounted in 1 of the 2 mentioned locations? I really need to put this in soon. Thanks again.

mike-2ptzero
06-29-2007, 07:23 AM
Lol at the disco ball. Throw some techno in and you've got yourself a little in-car rave action. Thanks for the info. I've read downstream was the ideal spot as well, but I was wondering if there's an actual "sweet spot" of sorts for it? Also, how can it be mounted before the cat? Onto the exhaust mani?? Post cat tuning does seem like a relative issue to look at when using one of these. It does make sense that your readings may be altered being mounted after the cat, but to what degree? Mike? Kompressed? Any thoughts since you both have yours mounted in 1 of the 2 mentioned locations? I really need to put this in soon. Thanks again.

It isn't going to make a huge difference if you put it after the cat, most dyno shops put one at the tail pipe or some where after the cat and the readings are just fine.


You cant put it into the manifold since that will be way too close to the engine. So it should be put down stream but still more then 8" away from any opening. Dont want it close to a opening because at idle the readings can be wrong from the fresh air being sucked back into the exhaust pipe during idle.


I had mine mounted right after the turbo, but it threw off my readings when there was a misfire causing me to think my car was running lean. All the tuners and turbo shops say the correct spot is further down stream so thats why mine is mounted after the down pipe now.

k0mpresd
06-29-2007, 09:31 AM
It isn't going to make a huge difference if you put it after the cat, most dyno shops put one at the tail pipe or some where after the cat and the readings are just fine.
it is a well known fact that tailpipe sniffers are not 100% accurate

they 99% of the time read leaner than what actual a/f is...especially if you have a catalyst in your exhaust

mike-2ptzero
06-29-2007, 09:41 AM
it is a well known fact that tailpipe sniffers are not 100% accurate

they 99% of the time read leaner than what actual a/f is...especially if you have a catalyst in your exhaust

True but that is also 10 ft futher down stream then the bottom of the down pipe so the EGT's are decreased, velocity is slower and the readings are going to be delayed if recording rpm at the same time. This is why most tuners say the best spot is just after the down pipe so you dont get false readings like you would right after the turbo.

b5gen
06-29-2007, 11:18 AM
haha, thanx guys.. some asshat told me it was the grey b4. i really have no need for a wideband yet. although im not oblivious to the ++'s of having a wide.. thnx lot

Side-Step
06-29-2007, 11:25 AM
Was just watching all the videos on www.innovatemotorsports.com
Pretty informative videos and they even have a forum to ask questions.

You guys should look at this site.

iin10ded
06-29-2007, 01:56 PM
so if mounting further away from the turbo, it's ok if there's a HFC in the way?

_audible_
06-29-2007, 07:06 PM
Hey thanks for all the info. It's helped me out quite a bit with this.

mike-2ptzero
06-29-2007, 08:14 PM
so if mounting further away from the turbo, it's ok if there's a HFC in the way?

Yes that is fine it wont cause that much of a difference in the AFR reading.

EuroIP
06-30-2007, 12:09 AM
let me know if u need wiring diagram
info@eipracing.com

thank you

Paul