Condensed into one post

Gave it straight battery power. 12v.

The ground wire when its not grounded says 9.5v.

Does this seem wrong to anyone else? With no ground, shouldn't I be seeing 12v at the ground wire? I have a feeling one of my wires is rubbing against ground or something...

Sorry, perhaps my advice is misplaced.

Did you try grounding it to the engine block, or close to an engine ground wire?

Refer to post above to see why I have not done that yet.

I accidentally gave the LED 12v and blew it up lol. Anyway after yanking on some wires, my gauge reads the normal 21.8 when full lean (compared to the 21.4 it used to read full lean), but I just looked at the signal and it still looks kind of noisy. Actually, pretty much identical to what I posted in the OP. I'm about to ready to rip this out and start fresh.


So the instructions as everyone knows, say to ground all the wires to the same ground point. You guys are talking about grounding the heater and signal to different places. What wires are these and why should I not be following what the instructions say when every thread I've searched says to follow the instructions? The blue and the white wire along with the black wire from the gauge are grounded at the ECU ground wire, all together. I'm getting power for the gauge and the LC1 from blue/black wire that powers the radio.

What am I missing here?

On top of that, trying to find the power window 12v source for the LC1 only made me realize that....my car does not have it. The connector that I expected to find is gone. I can't even find the damn wires. Does anyone know with certainty what colors these wires are on a '92?

By adding a ground, do you guys mean just running an extra wire from those 3 ground wires to somewhere on the chassis?

adding a ground would mean running a ground wire from the engine to a new location on the chassis. In this case the suggestion would be to put the ground close to the LC1 ground (or better yet crimp/solder a long ground to the engine).

I am pretty sure you don't need that calibration circuit, depending on the AFR gauge you are using.

I have to say I am glad I got an MTX-L, ---- was easy.

The MS1 has separate power and sensor grounds? Where are they grounded?

Here's what I might do.

All power grounds to a given lug on the engine block or head. MS, and LC1 blue wire both.

All signal grounds to a 2nd lug on the engine block or head. MS, and LC1 white wire both.

When I had noise issues on my aem wbo2 I just ran a new ground from the gauge to the stock grounding point on the engine and that cleared it right up.

Uhhm, My MS1 is grounded wherever the stock ECU is grounded.

Just to clarify, you're saying LC1 blue wire and LC1 white wire to the block on 2 seperate lugs? Even though it's a 6 wire (not sure if that changes anything)?

And which MS wires are you referring to, right now both the blue and white wire are on one of the MS ground wires, and I don't know where exactly that ground wire goes. Nor do I know which one is a sensor ground or power ground.

What I was going to do was run an extra wire to the block from where my MS ground, LC1 blue and LC1 white wire meet.

I'm too damn busy to work on this car, as you can tell from my delayed responses. :vash:

I'm also finding this out. Its WAY off on HPTuners. Can't you adjust the offset with the Innovative products but not the AEM unit?

Well, a select few of them do.

I suspect perhaps he was speaking of the LC-1, however. It has separate grounds for the heater and the logic/analog section, and while Innovate suggests that they be grounded in common, I suspect that grounding the heater separately and the analog/logic section to the ECU (as near to the ECU itself as possible) would be cleaner.


No. The AEM UEGO does not allow fine-calibration of the analog output. This is one reason why I vastly prefer the Innovate product.