okay i am running uberdata, and i am looking into the plx m-300 wideband system. I have a p28 ecu on a d16z6, now i am trying to find a way to wire in the plx into my uberdata datalogging software, and at the same time have it mimick my stock O2 sensor. I'm sure someone has done this before, where did you find the wiring diagram and such, i went to plx's website as well and their installation instructions are far from detailed. I also went to moates.com with the write up the guy did with his wideband but i dont know how that compares the plx unit. If you could shed some light on the situation please get back to me, thanks in advance.

 

You might find a lot more help on the UD forums...

Im not 100% sure about the PLX but you should be able to output either a wideband analog output to the ECU or narrowband, depending on how you set it up using the PLX software.

When tuning, use open loop and the wideband input to the ECU. When you arent tuning, enable closed loop and feed the ECU a narrowband signal.

 

okay, so i would kinda have to have a switch in the line somewhere, and the plx system has a wideband and a narrowband output

 

anyone else?

 

Post on uberdata, all answers can be foudn there. That is why it is a support forum, so you can do some research. LoL. but I think the pin you are looking for is D14...

 

yeah you have to solder in the 2 resistors on 2 certain pins, i belive one is the o2 heater, and you will need to cut d14 and hook the white wire from the plx into it, i know there is an answer in the uberdata forum for this

 

okay thanks, i know uberdata can bypass the the O2 heater function, but i will check it out on the other forum

 

yea, all you do is uncheck the heater and go into disable closed loop, and hook either one to D14, you can datalog right off uberdata with the wideband output.

 

I just chopped the tail off of an old oxygen sensor and wired the wideband output to that.

 

you can do that and then just disable the O2 heater, and closed loop and it will work fine?

 

bump

 

that is correct.

 

I have Uberdata and the PLX m-300. So do as I say!

The plx m-300 has two outputs: and wideband signal and a narrow band signal. We will be using the wideband signal and solder it onto pin D14. Now we will open uberdata and choose to disable the 02 heater so the CEL won't light up.

Believe it or not your done. You will probably want to run only is open loop from now on so go ahead and also check off closed loop disable box.

Your done. Not hard to do

 

You can run closed loop if you want to. What you need to to is run a switch. wire the common leg of the switch to d14. Run the norrow and wideband output from the plx to the other 2 legs of the switch.

When you are datalogging/tuning disable closed loop and flip the switch to the wideband output from the plx. When you are done tuning, enable clsoed loop on uberdata and flip the switch to the norrow band output from the plx.

Adding the switch might increase the resistance in the signal line so you will want to verify that what the plx is displaying and what uberdata is reading is the same.

 

Can someone help explain whether it is critical to go closed loop once we are done tuning?

Why not leave it at open loop. Does the ECU still need narrowband output in order to compensate A/F ratio although it's already tuned to 12.5:1 at boost?

 

tune your a/f in part throttle and you can leave your car in open loop all the time.

 

Is it safer to go back to closed loop (with simulated narrowband output from say, PLX m300)?
just in case it goes lean for whatever reason?

 

not really..it's a pain in the *** since when you tune you need the wideband input into the ECU and the narrowband into the same spot when you're not tuning and just driving. It's really not that hard to tune for partial throttle. If you check on the Uberdata forums (which are down right now) look for EZfuel version 1 or 2 it does all the partial throttle tuning for you. don't use it for boost though as it's just safer to do it manually (which is also easy to do). GL