AFR Wont Work On Megasquirt
 

Car Runs So Lean But I Can't Fix It Because Afr Wont Read On Megasquirt I Tried Calibrating It I Looked Up So Many Yt Videos To See If That Can Help Nothing The Afr Reads On The Gauge But On Megasquirt It Wont Read Nothing It Just Sits At 6.90 And Wont Move Also I Tried The Custom Linear WB That Still Wont Work .. Just Need Any Help

The AFR gauge has a 0-5 V ouput. Check to see that it is giving something reasonable, and changes from idle cold start to idle warm.
The maker of your AFR may say what to expect as outputs with no sensor attached, etc, which helps this test.

Otherwise, you may not have connected to the right input on the MS.
Or, you are looking at the wrong channel in the software,

Worst case, your MS input signal converter is no good. But that is not the place to start.

I Found Out What It Was It Was The Wire That Connects To The Old O2 Sensor That Wasn't In All The Way Now The Afr Actually Moves But It Still Wont Work Correctly On Megasquirt It Sits At 7.50 Then When I Press On The Gas Afr Goes Up To 10 And Stops At 10 I Think It Could Be A Wiring Issue But I Have No Idea And Icedawg Thank You For The Response

Did you calibrate tuner studio for your particular wideband?

I am a bit lost as to what you actually have. You mention readings on a gauge, but then you talk about using the old O2 sensor.
I assumed you had a new wide band sensor in place, and were not using the original sensor.

The original sensor is a narrow band sensor, with leads that go into the stock wiring harness.
So how are you getting the original sensor to go to the gauge? Or are you?

An aftermarket wide band sensor would connect only to the gauge, then you would send a lead from the gauge to the correct input on the MS ECU. In which case a loose wire on the "old sensor" would not make any difference. So I am a bit lost on what you are actually doing.

If you are using the MS to read a narrow band sensor you have to set it up in the programming to be reading a narrow band.

I am speculating that OP used the wideband output from the gauge and wired it into his engine bay to the harness for the stock o2 sensor wiring and him saying it was loose was in reference to the connection at the o2 sensor harness.

Its Hard To Explain Through Text So I Just Made A Video
If Anyone Could Help That Would Be Great

I understood your description of the problem you observe, so the video did not change much.

But I don't understand your set up. To help, I still need you to answer the questions I asked you above; about what sensor, what old sensor, how is it wired up, and so on?
I will mention that I had trouble getting the MS tuning software to show the right AFR display, there are multiple choices with almost the same name, and I kept choosing the wrong one when I started. So experiment with that.

Your innovate gauge readings don't make much sense to me, 7 at idle is "stupid rich" and 22 is "stupid lean". So there are a lot of strange things you observe right now. I expect it is in wiring, connection points for the MS, and set up in Tuner Studio. But, sometimes the new sensor is faulty right out of the box.