Hello, so recently I have purchased a AEM Uego wideband (30-4110) to go with my MSPNP2 on my 94 miata, and have only had it working correctly for an hour if that. At first I installed this gauge a few days ago, and it seemed ok, until about an hour later it got stuck on "- - -" maxing out at full lean. The next day, the gauge was stuck at 14.7. When I'm on the highway, it will stay around 15.1-15.4 for an AFR reading, and wont change much if at all when I decelerate or accelerate. I have checked all my wires and connections and everything seems to be good. I have replaced the stock o2 sensor completely and am not using the stock o2 plug. My ground is on my window control switch, power is switched 12v at my radio, and white wire is connected to my ECU, with the blue wire just hanging out behind my dash. What would be a logical next step? Thanks!

 

I have the same problem and same gauge, haven't gotten to get the car on the road with it though to start tuning, so I don't know if it will move from 14.7 but before I installed the turbo and MS3 the gauge would lean out during narrowband emulation like you mentioned. I used 12V from my door buzzer, grounded at a metal piece near the kick panel under the dash and fed the output wire to the o2 connector on the wiring harness in the engine bay. I'm thinking the ground is supposed to be on the head or intake man. I am getting an AFR reading on TS though

 

You want a very good ground for your WB. Switch the ground to the chassis ground pin on your MS options port, see how that fares. Also make sure the signal output wire is plugged into the MS all the way, it's a bit finicky. You'll hear it click once it goes in all the way.

 

So I'd have to plug the o2 signal directly into the ecu, not run it to the o2 connector at the engine? I thought the O2 in was that stock connector, not another port on the ecu

 

At the shop now... I have my options plug, I I'm going to continue using the buzzer for 12V, then ground at the sensor ground pin on the MS options port and use the Analog 2 pin for the signal since it is an option to use for EGO in TS

 

The gauge still stuck at 14.7 and now TS is stuck reading 10.0afr
edit: gauge is moving between 14.6 and 14.7 now

 

After letting the exhaust cool off I had taken the sensor out into fresh air and covered it with a rag of brake cleaner, nothing changed. then I unplugged the sensor and the gauge still did the same thing. I checked connections at the back of the gauge and the ecu and those were all good. What else is there to check?

 

We have the same gauge. 12V from switched power. Ground into ECU pin Chassis ground. WB input goes into the WB pin. I want to say the WB and GND are pins 5 and 21 (or reverse). WB has it's own port in MS, you don't need to use anything else to substitute for a WB input. The 0-5V wire is what goes to the MS, not the 0-1V. There's also a rotary switch on the back of the gauge, that needs to be in the right position. Should be P0? Your WB will flash Pxxx when you first start it up, that's what tells you it's in the right mode.

Wiring for the input will go as follows:
O2 sensor -> gauge -> MS
O2 has to go to the gauge and then into MS.

If you unplug the gauge it'll read 14.7, then accelerate up to full lean. That's how mine worked when I had it hooked to PWR/GND but hadn't installed the sensor yet.


MS has the right WB selected and calibrated right? AKA it knows it's a AEM 30-4110 and not any other gauge.

 

Here is what I have in my pin out diagram for the MS3Pro. Connectors 2 and 3 do not exist on my wiring harness, just 1 and 4 from factory as well as the options plug. Before I left yesterday, I changed the ego sensor selected between the two AEM options, nothing changed, then i just selected custom and put in the the values in for 2 different points on the afr output. I think I should've tried the 14Point7 or no? I think my problem would have to be the signal wire input and port selected for it. what pin from the diagram did you say was used for the WB 5V?