91 Turbo Header Install Question...O2 Sens Location
 

Hello All, I plan to install my headers in the next few weeks, GSF w/o heat to be exact. SO....I am looking under my car and of course, a pic of the headers. Where does my O2 sensor go? Looking like I need to weld a bung in for it from what I can see. I am taking a guess it would go in the pipe that runs between the turbo and the wg? Am I correct?
Currently (stock) it's not located their, I am going to say it's sort of "in between" if that makes sense...Gawd I feel stupid with these cars sometimes...I can work on old muscle cars almost blindfolded :) Thanks for any help, just doing some pre-planning is all.

OK, I just had another look, I suppose my O2 would be 'post turbo' and it appears, at least what I see in the picture, their is a bung in place already right where the turbo flange is "pre turbo"? Is this right? If so, am I cool going "pre turbo" on my 91' ?

if you are talking about an aftermarket wideband 02 sensor for a gauge, then you go after the turbo about 6". also you want to mount it on a slight angle if its a wb02

Hmmm, Now You just brought up another point I didn't think about.
I am also installing the PLX DM5 AFR Gauge/Kit simultaneously, which means the supplied WBO2 sensor will completely take the place of my current narrowband/standard O2 Sensor. Am I OK mounting it as You described? Meaning it will handle the "stock" function as well as delivering the AFR readings to the gauge in Wideband (It simulates a narrowband signal to keep the stock computer happy, just FYI in case not known). Thanks

i am not familiar with the specific model/brand you are using but I am under the impression the wb02 will only work for your gauge and tuning and you would still need a narrow band o2 mounted before the turbo to work with the cars computer.... I am just guessing on that though, my car is older then yours and does not have narrow band 02 sensors so I am not sure what they are hooked up to exactly...but on newer vehicles that use narrowband 02's to adjust fueling with the computer you need to leave those or you end up with the check engine light always on...unless you get a casper 02 simulator

Some of PLX's Sensor Modules and sensors will do Narrowband emulation along with the WB reading. It is hit or miss whether that will work for you. Some people sing the PLX get it to work, some don't. They have Docs on their site about this. You may want to call them, they are very helpful. Y

ou want your wideband after the Turbo. Some folks say that arrowbands work better before the turbo because they stay hot and so forth. Not entirely certain i agree with that. Everybody says to put the WB after the turbo.

Hope that helps.

If I were you, I wold have another bung welded into the muffler inlet and mount your WB there and leave the factory sensor alone.

Les

Ahh, I am going to do the bung after the Turbo i suppose and roll the dice. I have heard nothing but good about PLX on many different forums so I'll take the chance, It will probably work fine, no worries...yet at least :)
My current O2 is after the Turbo so that seems like the right thing for me to do all-around.
Thanks for the tips, as always, greatly appreciated.
Wait 'till the full rebuild at years' end...I'll be posting plenty :eek:

Hmmm, let me rephrase then. If your current sensor is after the turbo, then I would read the docs at PLX and put their sensor in that position to do WB and NB emulation. Who knows, you may get lucky and get it working. I'd definitely give it a shot. You could then run one sensor that would display on the PLX and send a NB signal to your fuel system.

Les