So I finally got my ms3 pro pnp and hooked it up tonight, excited to finally get to tuning, until... tunerstudio just gets no reading from my wideband. I've tried calibrating it with every aem option available, as well as manually inputting the voltage/afr ranges (0v=10afr 5v=20afr). Now my Guage reads seemingly pretty accurate, and upon testing the output wire the voltage rises and drops seemingly accurately, so it seems to be in working order. I currently have it wired up just using the stock harness (white aem wire to the blue wire on the wiring harness). This all was working flawlessly on the stock ecu for many days now, yet it suddenly isn't now. Upon some testing I found that whatever I set the lowest afr reading to in the calibration menu is what tunerstudio reads, i.e. 0v = 10 and tuner studio will read 10.3, or I put something like 0v = 5 it will read like 5.5. Essentially tuner studio is showing that its getting close to no reading from the wideband. Tomorrow I plan to swap back to my stock ecu and just see if that still works in order to help deduce if it's the wiring between the o2 sensor connector and the ecu suddenly and spontaneously going bad, or if it's something ms3 related, however any tips as to what could be causing this would be greatly appreciated. I've looked around online and I have seen some people mention that certain versions of the ms can't read wideband readings from the stock harness, however given I have the ms3 pro, I'd assume it should be able to. Sorry for the lengthy post, but I just wanted to be sure I was as thorough as can be. Worth noting that I've tested this with the gauge set to each of the different "emulation" modes it offers, as well as its regular wideband mode and it didn't change a thing.
Car is a bone stock 97, and the o2 is an AEM EUGO wideband (30-4110).

 

So update, upon putting the original ecu back in it's working flawlessly. If I switch the mode on the gauge from narrowband emulation to any of the other modes, it immediately causes the idle/revving to be extremely sporadic, leading me to believe that the wideband is making communication with the ecu, just that for some reason the megasquirt won't recognize it. I checked the pinout diagram for the ecu and it clearly states that the megasquirt can accept the o2 signal from the oem wiring. I'm gonna try and fiddle with tuner studio to see if maybe it's something with tuner studio, but I really doubt it. If I can't figure it out that way then I'm gonna go ahead and wire the wideband output directly into the options port on the megasquirt and see if that fixes it.

 

Did you ever figure this out?

 

Yes, but i have absolutely no clue what I did. I dont even remember having this problem. I've since switched it out for one of the AEM X widebands running on CANbus. 1000x better than an analog gauge. I assume you're having a similar problem to my original one? Tbh I probably had it wired wrong or something..

 

im on 2 AEM 30-0310’s they were working fine and randomly stopped working, tried new sensors etc no luck

 

have you double checked all of your wiring?

 

Triple checked everything, it was weird because they started to go full lean before they stopped reporting data, that came with a full on “misfire” engine runs like crap right now. Mind sharing your settings for the widebands via canbus?

 

Yeah, I can look when I get home. Are you using EGO? If not, then your wideband going out shouldn't cause any issues.

 

Nothing in settings changed I even went back to my original tune from when I got my car back from builder - when everything was working fine and still no luck.

 

I believe these are all of the relevant settings when it comes to CAN communication. It sounds like the sensor itself may have gone out, however I do find it pretty strange that it's causing the car to run poorly. I'd disable EGO if you have it on, at least until you get this resolved.