upstream o2 sensor issues

[Dayonaise]

So here's the deal, bought a 97 tsi awd with a 90 6 bolt swap. Runs great until about 4000 rpm then bogs hard, so i had a look around and found there is no o2 sensors through the 3" straight piped exhaust. Now my issue is i have read that i should install it 36" from the exhaust port on the turbo and i have also read i can just use the stock location because its not a wideband system just a stock sensor. Is this correct?
Also i have not been able yo find the o2 harness anywhere i do know what the 97 harness looks like but no idea where its supposed to be and yes i have searched countless threads and sites. And I'm unsure if I'm looking for a 97 harness or a 90 harness because of the swap, are they in different places? I appreciate all the help i can get thanks.

Oh and i do have an autometer AFR gauge that as far as i can tell is not wired in or has been snipped

 

[inspire]

Is it possible that the connector is missing? A missing connection or a damaged wire would cause for 02 failure and make the car run very poorly all throughout the power band.

 

[synthetek]

What kind of turbo / o2 housing does it have? Is the stock o2 sensor location on the o2 housing blocked off?

 

[WES_393]

The 36" is for a wideband sensor, not a stock sensor. Your stock front O2 sensor should be in the O2 housing, which is connected to the right-hand side of turbo. Regardless of year or brand of O2 housing (unless its some custom piece) it should be right there. The wiring for it connects to the engine harness near the coolant temp sensor wires. If the sensor is missing or the wires to it are missing, you need to replace it with an OEM sensor and pigtail. Not having a front O2 connected to the ECU will cause all sorts of problems, uncluding bogging and hesitation.

 

[Dayonaise]

I think i might have found it but not sure? It kinda looks like the female end of the connection
I will try to upload a pic if i can. Wire colors are RD/BK YL/BK WT/BK and BK

 

[synthetek]

Did you find the sensor in the 02 housing?

 

[Dayonaise]

I will also take a pic of where the o2 port is in the piping and yes its plugged

 

[synthetek]

I will also take a pic of where the o2 port is in the piping and yes its plugged

Are you talking about the downstream sensor in the exhaust by the CAT (or where the cat should be if you don't have one) or the one in o2 housing on the side of the turbo?

 

[Dayonaise]

I have no port on my turbo just a few ibchs below the exhaust port on the piping (downpipe?)

Won't let me upload the pics

 

[synthetek]

It should be on the o2 housing, between the downpipe and turbo, what kind of turbo is it?

 

[WES_393]

Upload them into photobucket and copy/paste the last link.

 

[Dayonaise]

20G hybrid, ill try photobucket

 

[WES_393]

Then yeah, you should definitely have a typical DSM O2 housing like shown below. Notice the bung where the O2 sensor should screw in.

 

[Dayonaise]

I think this is the link to the pic the port is just under my WSTG and has a bolt in it sorry its hard to see

20121122_172707.jpg photo by dayonaise | Photobucket

There is also a pic of the connector i found that i think might be it

I'm uploading a vid to YouTube as well so that I'm clear on what I'm trying to describe

So mine does have that bungalow on there does that been i have to run a wideband o2? And if not can i still use my AFR gauge with a stock o2 sensor?

 

[WES_393]

Ah, I see now. Whatever turbo you have, it has an external wastegate off the manifold. So you probably don't have a typical O2 housing like I showed. However I think I see where the sensor bung is plugged like your saying. That orange plug is also the factory O2 plug.

Now, the fact that the car hasn't been running a front O2 makes me think the previous owner spliced a narrowband input into the ECU to simulate a front O2. Yet you say there's no sensors, so it's a mystery what they were using. I would check the ECU plugs for any wires spliced in, specifically at the front O2 input (ECU pin out: http://www.dsmtuners.com/forums/articles-tuning-ecu/281763-2g-turbo-ecu-pinout-w-wire-colors.html) If all looks good, install a factory O2 into the blocked bung and plug it into the orange plug. That should restore the ECU's fuel control.

 

[Dayonaise]

Ok ill ha e a look in the morning at the ecu, i ordered a stock 97 o2 sensor today so ill put that in tomorrow too. And ny ecu should be here tomorrow from dsmlink with the v3 update so ill slap that in too.
Thank you everyone i will post my findings as soon as i can.

Oh forgot that my current ecu and my linked one are both 1990 1g

 

[synthetek]

Why does your car have a 90 ECU?

 

[Dayonaise]

Cause its a 1990 motor and 90 harness i do believe. Unless the PO has misinformed me about the harness and ecu

I will check the ecu numbers when i pull it in the am to make sure

 

[We're on Boost]

If it helps any, here's a hi-res pic of a stock 1990 setup with a brand new OEM O2 sensor (narrow band) installed in the stock O2 housing. You can tell this is one of the first things that was done on my car. The sensor is the only clean thing in the pic!

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[Dayonaise]

That does help lot thank you
I took a pic of it from the bottom and it looks the same

Installed the new o2 sensor and voila she's alive, who knew Haha.
I believe i have some boost leaks to fix and figure out how to run my 90 ecu in this car but I'm sure i have seen sonera threads ob that stuff so back to searching.
Thank you to everyone that helped i appreciate all your input and very quick replies.

 

[synthetek]

Cause its a 1990 motor and 90 harness i do believe. Unless the PO has misinformed me about the harness and ecu

I will check the ecu numbers when i pull it in the am to make sure

If you bought a 97 o2 sensor and the plug fit then you probably don't have a 90 harness, the 1g/2g o2 sensors have different plugs. A lot of people swap to 1g motors but they usually don't swap the harness and ECU.

 

[We're on Boost]

Installed the new o2 sensor and voila she's alive, who knew Haha.

Good deal!

 

[Dayonaise]

Yes the 97 plug is what was there so i take it the harness is a 97 as well as ecu, I'm thinking of not using my dsmlink 90 just so i don't have issues with the pin swap. Also my car is still flooding i believe from about 2k to 4500k then smoothes out and she flies all the way to redline. Still can't figure out how to hook up my af gauge cause the wires are chopped but I'm sure its running too much fuel when i step on it and really jumps around

 

[We're on Boost]

Yes the 97 plug is what was there so i take it the harness is a 97 as well as ecu, I'm thinking of not using my dsmlink 90 just so i don't have issues with the pin swap. Also my car is still flooding i believe from about 2k to 4500k then smoothes out and she flies all the way to redline. Still can't figure out how to hook up my af gauge cause the wires are chopped but I'm sure its running too much fuel when i step on it and really jumps around

Hmm, and your Linked ecu is a '90. So now I guess the big question is whether to rig a harness to use your 90 ecu, or go with a 2g ecu. And that is way beyond what I would know how to do - either way.

I see WES posted a link to a 2g ecu pinout above. I can post a 1g pinout (partially labeled) here so you can see that they are quite different. They don't even have the same number of plugs. Not to mention that 90-94 is OBD1 and 95 and newer is OBD2. Wow.
On the 1g pinout there is the additional problem that there is a slight difference between the 1990 and the 91-94 ecus - there are 2 pins that are swapped around, I don't remember which ones they are. So the diagram I'm showing below I think is actually for the 91-94.

Hey I see you have over 30 posts now. You should start a thread in the engine management section, get the heavy artillery in on this problem!
Here's the 1g ecu pic:

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On the A/F gage, do you mean that you hooked it up and it is jumping around? I know that one of the Autometer A/F gages is for narrow band (like stock) sensor - and they are pretty useless. Jumping around is what they do! If you have an autometer part number for that gage you should look it up or email the part # to Autometer tech support to find out if it is designed for narrow band or wide band O2 sensor. Autometer tech support by email is actually pretty good. Much better than most. In fact some outfits, like AEM (I think) don't offer any tech support at all. They have a user forum which they call their "tech support". Kind of going by memory there but that's one reason why I never bought an AEM EMS for engine management.

 

[Dayonaise]

Ya I have decided to sell my 90 ecu and buy a 97 with v3 link, as for my AF gauge I havent hooked it up the wires were cut just under the dash and i dont know where it was hooked up previously?
and I thought it was an autometer but thats my boost gauge, my AF gauge is an EQUUS gauge.
I am trying to upload a video that i took a couple days ago when i started this thread, there is a connector harness in the video just under the steering wheel that i have no clue where it is supposed to go. once the video has finished uploading I will post it please let me know if anyone knows what its supposed to connect to.
I think the PO was a little snip crazy with the wires during the swap.