Wiring for both WB and NB at same time

[Vettepartz]

I have the HPTuners MPVI Pro and am looking at getting a Wideband setup. Probably gonna be either a PLX or the Innovate LM-1. I am wanting the ability to plug the sensor into the existing bung (pre-cat) and use both WB and NB outputs for tuning. Can a pigtail be wired into the sensor connector to plug into the vehicles wiring harness where the original stock NB was and still function as a NB for the input needed to the PCM? If so, what mods would be needed and which Wideband Product would you use? Thanks for any help.

[Dirty Howie]

I have the HPTuners MPVI Pro and am looking at getting a Wideband setup. Probably gonna be either a PLX or the Innovate LM-1. I am wanting the ability to plug the sensor into the existing bung (pre-cat) and use both WB and NB outputs for tuning. Can a pigtail be wired into the sensor connector to plug into the vehicles wiring harness where the original stock NB was and still function as a NB for the input needed to the PCM? If so, what mods would be needed and which Wideband Product would you use? Thanks for any help.

Go on the PLX site. They have a good document on there that explains how to hook up theirs to give WB and NB readouts.


DH

[Vettepartz]

Thanks Dirty H, but I couldn't find that document on the site unless it is a reply in one of their forum questions.

[Dirty Howie]

Thanks Dirty H, but I couldn't find that document on the site unless it is a reply in one of their forum questions.

Try this link:

http://www.plxdevices.com/AppNotes/PLXApp004.pdf


DH

[Vettepartz]

I am looking to use the connector that is already on the car's wiring harness which normally goes to the O2 sensor. It looks like the PLX diagram has a wire from their SM box to the ECU. I guess I am looking for a way to tap into the new wideband sensor wiring and connect that to the wiring harness sensor, if that is possible.

[Dirty Howie]

I am looking to use the connector that is already on the car's wiring harness which normally goes to the O2 sensor. It looks like the PLX diagram has a wire from their SM box to the ECU. I guess I am looking for a way to tap into the new wideband sensor wiring and connect that to the wiring harness sensor, if that is possible.

The support over at PLX is pretty good. I would call them ......


DH

[seven ends]

I am looking to use the connector that is already on the car's wiring harness which normally goes to the O2 sensor. It looks like the PLX diagram has a wire from their SM box to the ECU. I guess I am looking for a way to tap into the new wideband sensor wiring and connect that to the wiring harness sensor, if that is possible.

I did the sacraficial O2 and wired the pigtail. Used the PLX instructions plus vehicle tech manual information to connect. Added the noise filter capacitor at the interface box for the output and ground and then another one at the input and ground.

Also got a project box, breadboard, automotive conduit, stick on cable shoes, and two 10 ohm resistors. Wired assembled resistor box in per PLX instructions. Probably could have left this step out if I had the HP Tuners before I installed the WB. I still got the random light, metered at 20 ohms, so not sure if I needed more resistance or what.....but it was easy to just toggle the light off....and left the resistor setup in place since it was already done.

Other than soldering the resistors parallel to the breadboard, everthing else was crimped and heat-shrinked. On the signal wire this is very important that the signal be clear. There is an age old debate about solder vs. crimp.....but bottom line it is easier to be perfect with a crimp than a solder joint.....in most cases. Also, for the signal wiring I made sure to get new wire the same size......not taking a chance on losing some of my signal voltage because I grabbed any old scrap wire laying around in the garage.

You will read in the PLX instructions as well that grounding in the right place is important too. The output signal ground was a no-brainer. However, for the input signal, since I was using the pigtail....instead of grounding back through the pigtail.....I grounded to the same strap grounding point as my PCM. And don't forget the capacitor.

On capacitors.....the ones PLX provided had short legs.....so I opted for a pair with longer legs from Radio Shack. The part numbers for the resistors and capacitors are in the PLX instructions.

After the install, I would meter the results of your work to make sure your voltages look in line.

If I had it all to do over again, when I changed out my headers, I would have dropped the Y out and had a new SS bung (with plug) welded in at each exhaust flange (before cats). Then all the work above to replace a NB would have been Null.

Good Luck,
Tomy