Aftermarket Wideband to Rear O2 signal

[yomny]

Originally Posted by Sportsguy83

You will connect your O2 Wideband in the slot where the secondary O2 is palced from factory.

You will connect your Wideband gauge connection as normal, from the O2 harness into the Wideband gauge inside the car.

Now, you need a Wideband gauge that has a 0-5V output cable (example FAilsafe gauge). You will use the Wideband output 0-5V cable and connect it to Moto Mike's harness, and will plug said harness into the car's stock rear O2 electrical connection.

I wish I had that option available when I did mine, it looks very clean.

Not sure if you know but does the harness from Moto-mike have just one wire coming out of its connector for the 0-5v ouput or it has that power/ground others are mentioning?

Thanks a bunch..if made any simpler you'd have done it for me lol. Thanks man.

[Sportsguy83]

@moto-mike So with that harness do we just remove the factory rear O2 harness altogether, plug the connector into the now vacant slot, then crimp the other end of that white wire to the analog signal wire from the wideband gauge......yes?

That's correct. Just make sure to disable rear o2 learning and codes as mentioned elsewhere in this thread.

Originally Posted by yomny

Not sure if you know but does the harness from Moto-mike have just one wire coming out of its connector for the 0-5v ouput or it has that power/ground others are mentioning?

Thanks a bunch..if made any simpler you'd have done it for me lol. Thanks man.

No problem, I'm always willing to help.

Looking at wowy attached image, and Moto Mike response above, it seems that yes, it just includes the wire for the 0-5V input. I don't think the power/ground cables are needed, just need to turn of DTC in Ecutek for the rear O2 and thats it.

[yomny]

@Sportsguy83 The idea of doing this is for the failsafe trigger but also for tuning? Now the wideband signal could be used by ecutek for tuning? Thanks

[Xero-Limit]

Originally Posted by yomny

@Sportsguy83 The idea of doing this is for the failsafe trigger but also for tuning? Now the wideband signal could be used by ecutek for tuning? Thanks

Yes, you actually don't need the AEM failsafe map because you can make a 3d map with RaceROM of load vs rpm vs AFR. Then layer it with a secondary map to add fuel if it is too lean. This is essentially closed loop fuel control but without giving the ECU the leverage to lean it out so it won't pop the motor if the sensor goes bad.

Lots of work, and realistically very little to no gain, but if you have a clogged injector or overboost beyond where the tune is designed, it can save your motor.

[yomny]

@Sportsguy83 So the wire we connect to the secondary 02 connector is the Wideband white analog for AFR not the blue one(failsafe).. and then the values in the table you provided in the first page for the voltage calibration from AEM are entered onto Ecuteks tables? I think had the wires coming off the AEM failsafe wideband confused. The white one is the AFR output we use, the blue one is a failsafe output.. but i was confusing this since the one on the ECU that receives input from the 02 wires is blue.

[yomny]

Been looking around and can't seem to find which fuse under the dash panel is used for the 12v ign and for the dimmer? Thanks

[ztan]

For those of you wanting to log with Tactrix OP2, you can wire your wideband signal to OBD pin 12 which is unused in our car. The ADC in the box can read voltage off pins 8, 12, or 16. Pin 12 is connected to the tip of the 2.5mm jack also if you don't want to hardwire - but it is a pain plugging and unplugging every time.

I've put a PLX Bosch LSU 4.9 sensor in, wired the 0-5V output to pin 12 on the OBD plug, and wired the 0-1V narrowband output back to the rear O2 input plug (with a 20 ohm resistor across the heater terminals). Works great.

I like the Tactrix OP2 for logging. Small, fast, unobtrusive, and I can analyze all my logs in a large batch quickly with Matlab.

[burdickjp]

Originally Posted by ztan

I can analyze all my logs in a large batch quickly with Matlab.

*shudder*

Ever played with python?

[yomny]

I use Megalog viewer from EFI analytics to read logs, works nicely.

[burdickjp]

Originally Posted by yomny

I use Megalog viewer from EFI analytics to read logs, works nicely.

I've used it for a long time with Megasquirt, but never with anything else. It is an AWESOME squiggly line program, and I love their scatter plots.
Thank you for sharing. I'll look into that further.

[SunkenFRS]

Has anyone figured out how to wire this up with a p3 gauge?

[buddy32]

I've got the Ptuning turbo kit, and the turbo downpipe directly behind the turbo has an O2 bung on it. That's where I've installed the AEM wideband UEGO sensor. I t-tapped the white wire to the back of the ECU on A34 and the brown ground wire to the ECU O2 ground, pin 7 on A35 (top left of pin A35).



If I unplug the original 2nd O2 sensor in the engine bay, I get the following three codes.



If I plug it back in, with the blue wire on it disconnected, I only have P0138.

In ECUtek, I've observed the voltage reading to be higher than 4.5V. Has anybody experienced this problem? Suggestions for fixes? Opinions on O2 spacer such as the following?



@Sportsguy83, @spdbydesignchris, @King Tut, @moto-mike, @ptuning

[King Tut]

This is a question best asked of an EcuTek tuner. My understanding is that in EcuTek you can tell the ECU to not check for the secondary O2 sensor and then you have to tell it what you want to do with the signal that is now input on that pin.

[Peace@Ptuning]

Hi There,

Ken and our tuner are already on this, We should have an answer for you really soon! If you need to find out progress or have any other questions, please contact Ken@ptuning.com

Thank you!

-Peace