I just got a wideband O2 sensor (AEM UEGO) and will probably start playing with it this weekend. I have a few questions.. I've read a lot on here, but there seems to be some contradictory information floating around so please bear with me. The questions are intended for any WBO2 users, not AEM specifically.

1.) Sensor mounting location: AEM states that it must be 36" after the turbo (due to heat), which at a minimum would put you around the end of the downpipe, or maybe the inlet area of the cat. Ideally, I'd like to get a bung welded on in this area, but until then (and on friend's EVOs), I'd very much like to use the stock location. However, AEM clearly states that it must be upstream of the cat to get good accuracy. A lot of people around here seem to use the stock (after cat) location though, so I'm wondering if anyone knows how much accuracy you are really losing.

2.) Longevity: Do most people do a permanent installation, or do you just hook it up for a 'tuning weekend', then remove it? After reading the AEM forums, I found that the life of the sensor can be fairly short (leaded fuel and heat issues aside), making me think maybe I don't want it permanently installed. Also, is there really any point in leaving it in? I mean, once you dial in your A/F maps and really fine tune them, do you really need to monitor them anymore? Do they vary with weather, for example (like boost does with a MBC), making you want to continuously monitor them? Or is it just for the fun geeky tinkering and modding that makes you want to keep it installed?

3.) I read that you should never leave the sensor installed and run the engine w/out the sensor being powered up.. makes sense to me. But then I also read that if you power it up w/out the engine on, you can damage the sensor. I'm wondering how true this is. Is it really that fragile? I mean, if I sit in the parking lot listening to the radio for half an hour with the engine off, will the sensor burn itself up?

Sorry for the newbie questions. Any opinions/comments are welcome. I've tried to search a lot before posting, but searching under terms like "wideband" generally result is more 'noise' than useful 'signal'.

Thanks,

Rob

 

1) My WB o2 (AEM UEGO gauge type) sensor is in the stock location in the o2 housing. We removed the narrow band stock sensor and replaced with the WB sensor. Though if you're running the stock ECU this would not work for you. If you're running a catalytic converter, you will want the gauge before the cat. For stock ECU, the best location is probably somewhere on the downpipe with a separate bung.

2) Permanent install! I don't know why you wouldn't want it to be there all the time unless you're tuning cars and need something portable. My WB has been in my o2 housing for over 1 year (never any leaded fuel) and it works great. It was on the stock turbo for ~11 months, on a 3076 turbo for ~3 months.

3) I'm not too sure on this one, but sounds like a myth to me.

 

Everything I've read indicates that the stock O2 housing (what's that, 4 INCHES from the turbo?) would be way too hot for the sensor. You managed to go over a year though. That's amazing.

 

It is way too hot for the sensor. Some get lucky and do not burn their sensor. It is generally accepted that you put the wideband before the cat and at the end of the downpipe.

 

I'm going to install mine in the extra bung I have in my testpipe.

 

I usually just use the stock sensor location. I dont have a cat so it does not matter. I take out the stock sensor and install the wideband, then tune, and remove the wideband and re-install the stock sensor.