Has anyone done this on an NNBS? I know KYSilverado did it on his truck, not sure if it'd be the same on my truck though. I'm trying to get my PLX install finished between seeding, spraying, and being a dad but I wanna eliminate my narrowband. And does anyone know how I can wire it into my pcm? And will that make the WB line in my HPT scan come alive? I've tried looking on the HPT forum but it's like another language over there. And it seems if people know they don't wanna tell you. Thanks!

 

if you want to monitor WB with HPT you need 1) a WB sensor. PLX?
If you want to run SD and turn off your trims this is called Open Loop Speed Density. Is this what you mean?

To get HPT to 'see' the wideband you need to run a lead into the HPT device.

 

I did this on my 95 not too long ago. The cam overlap was messing with the narrow bands ability to read correctly even after tweaking on the 02 voltage tables. It would run really rich at part throttle and very lean as closed throttle and under a load when there was a lot of exhaust flow it would read right. My PLX has a narrow band output that took the place of the 02 signal to my PCM. After a couple 02 table tweaks it ran perfectly on the wide band and ran at the targeted AFR in closed loop with fully functioning fuel trims. Not only that but it corrects so much faster now than the slow narrow band sensor could do which isn't completely necessary but nice feature. As much trouble as I had on mine with no bigger cam than I've got I can't imagine how some of you guys are running big lumpy cams and having any sort of accurate fuel control with narrow band sensors. I know its not just the fact I'm working with primitive OBD1.

 

A few years ago I had a PLX and cut a pigtail off an old pre-cat O2. I wired the new WB sensor into the pigtail taking into account the PLX instructions for simulating. After messing with some resistor setups to keep the O2 heater code off, I finally took the old pigtailess sensor and wired it to the simulated WB/NB harness heater wires and mounted it to a metal electrical wall box in the engine bay. Ran it that way over a year, no problems, PLX reported fine.

However, much simpler to weld a new bung in for a separate WB and leave the NB's where they are which is what I do now and I believe most do. My 2 cents.

 

Hmm, no I don't want to run speed density. Just thought it'd be good to eliminate an o2 sensor. But ya, I'll just run it separate.

 

Just so you know you are not ever supposed to splice 02 sensor wires between the sensor itself and its harness connector. On the vehicle harness is fine but not the 02 sensor harness itself.

 

Can you elaborate a bit on your warning considering Bosch and others who sells millions of universal O2 sensors that splice the harness to the O2. thanks in advance.