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AEM Do I need a tune after installing AEM Wideband?

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INSANEMAINE

Probationary Member
12
1
Jul 30, 2022
New_Mexico
I just installed my AEM wideband, I Installed the O2 sen in the front, i disconnected and wired in to pin 76, wired red wire to the cigarette lighter and black and brown wires to the bolts to ground it, i started up and everything worked normal, it showed 14.7, the car was only on for 15 mins, the next day i start the car it started to idle funny and it started to show over 20 and it just says - - -, i don't know if i need a tune or what, i have a 99 gst with original 99 black box and going to tune on ecuflash or evo scan. The car just stutters now and sounds like its going to stall while idle and shows - - - -. I'm going to install my 550cc injectors with 190 walbro fuel pump after i get this wideband problem fixed. everything is stock except air intake and BOV. I also just changed my MAP, IAC, Camhaft position sensor, and power transistor. My Eclipse worked perfectly before installing wideband. Any help is much appreciated
 
I'm not familiar with 2g ECU wire pinouts. But if it worked before you disconnected pin 76 to your ecu, I would suspect that to be the issue. And/or you removed the front o2 sensor as well. (which the car needs)

On my 1g, I replaced the front o2 sensor with a wideband sensor. To make the car work, I wired the narrowband simulator wire into the ecu in EGR spot, and had ECMLINK set to look for the o2 sensor data where I told it (EGR pin). So that it still has an o2 signal to run the car during closed loop, (idle and cruising).

If your wideband has a narrowband simulation wire, I hope thats what you wired into the ECU? If you did, you will need some way for the ECU to know where to look. (ECMLINK etc). Unless pin 76 is the front o2 circuit?


Basically, your ecu needs a narrowband input from the front o2 sensor. If you have removed it, you will need to run a narrowband signal back to that same circuit (can be done if your wideband has a narrowband output wire), or to an alternate circuit (I used EGR for mine) and ECMLINK or similar to tell the computer where to look for that signal.
 
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Okay, so you did tap into the front o2 sensor wire. If you're wideband is like mine, it will have 2 data wires. One for datalogging, and one for narrowband simulation.

Maybe you hooked up the datalogging wire (wideband signal) into your ECU.
In you're case, without tuning software, you would want the narrowband signal going to the ECU.

Let me look into the AEM UEGO and see what I can find.

Just to clarify, you replaced the front o2 sensor? The one right after the turbo correct?
 
Post edited to remove wrong info.

I know ECMLINK can run a narrowband simulation from the 0-5v input.
Not sure if black boxes can run ECMLINK though, ECUFLASH appears to have something similar
 
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BTW, the "----" just means a very lean condition. Like above 20:1 ratio. From everything I found on the X-series, you only have a 0-5v output. You may want to reconnect your factory front o2 sensor and wire, and use this in the rear o2 location for datalogging, when you get your tuning software setup.

Or you can switch to another wideband setup. People are really fond of the Innovate ones around here. That would allow you to not have to undo the work you did tapping into pin 76. You would just run the 0-1v narrowband signal to that pin. Because that is what the ecu expects to see like curt-s said.
 
If you are not running a tuning program, you need to run the car on the stock narrowband and install the wideband further down the stream to show you the exact AFR's. It may not talk to your ECU (your wideband) but you can tune by watching it as you tweak different things.
Put the original O2 sensor back in and you should be good.
 
Does not have ecmlink
Was written in 2010 and x-series was introduced 5 years later

OP, what exact model # do you have
If you are not running a tuning program, you need to run the car on the stock narrowband and install the wideband further down the stream to show you the exact AFR's. It may not talk to your ECU (your wideband) but you can tune by watching it as you tweak different things.
Put the original O2 sensor back in and you should be good.
Ok thank you I will try that, would this mean I would have to switch my pin from 76 to 75? Also model number is D32AMNGFL4M
 
Pin 75, yes. as Marty says, putting it on the rear o2 connects it, but it won't do anything unless your ecu is able to read it as a 0-5v linear wideband and even then you'd need to adjust it because, well, it's an AEM. Even those on ecmlink have to fiddle with them to get it to log the right AFRs.

However if you're on the stock ecu set up, it will definitely not allow emissions checks to complete as they use the rear o2 to ensure proper operation of the cat. You may or may not care about this. The stock ecu code cannot deal with a wideband in the rear spot in its stock form. It might even throw a code because most of us on ecmlink lock rear o2 voltage after doing this because of the voltage expectations from the cpu which the wideband is not complying with.

Sorry I meant gauge model #, that's a VIN for a (your) car.
 
For "sniffer" purposes, you could run the AEM as a standalone and still run the car on stock front and rear O2's if your car uses a rear O2 sensor.
 
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