TunerStudio / Megasquirt PNP not picking up AFR signal

[vtechnik]

Hi there,

I recently did some rewiring of my gauges, and while I was working on rewiring the AFR gauge I accidently pulled the AFR wire out of the external 26 pin connector.

I could've swore the pinout diagram said it's pin number 21 for an O2 sensor, so I rewired it into pin 21 on the connector. I reconnected my laptop with TunerStudio and I'm seeing that the readout still shows an inaccurate ~7 A/F on the laptop's gauge. This is strange to me though because my physical AFR gauge (which uses the same wideband controller) reads an accurate AFR. I checked the wire going to my Megasquirt PNP and it shows that it has roughly ~5 volts when the car is in the ignition position which would be something like 18 AFR (which is what the physical gauge reads) not the ~7 A/F that TunerStudio shows.

Am I missing something? I changed my EGO control setting to single wideband but it's still inaccurate. Is there a setting I missed to change the AFR gauge to read the external one and not the factory narrowband wire?

Also, can someone confirm that pin 21 is indeed the correct pin for the external O2 sensor?

Thank you

[Dj Buttchug]

What Version of MS are you running. Some later versions have settings/ calibrations for AFR depending on which one you are using (AEM INOVATE ect)

[vtechnik]

My TunerStudio MS version is 3.1.08, the MS PNP is a gen 2.

Which judging by that manual pin 21 is the right spot for an O2 sensor.

I went in to calibrate my AFR table in TunerStudio and I set the two points according to the manufacturer of the wideband controller (and pressed write to controller)

This picture is with the laptop disconnected from the car, I can do more screenshots or pictures connected to the car. The reason I suspect a setting is bad, is because 4 volts is 17 A/F, and while I can see that the wideband ecu signal wire in ignition mode has 5 volts, the laptop / ecu doesn't read anything above ~7 A/F even though my gauge is at 19 A/F (which I suspect matches the 5 volts the gauge signal wire is giving off)

The second image is where I set the EGO type to single wideband. Do I leave the 1st EGO sensor port to local, or do I change that to one of the Remote ADC[0-7]?

Thank you

[vtechnik]

Solved the problem! Apparently I also jostled the pin 5 wire out as well while rewiring. This is the ground wire for the MS to read the AFR input.

Thanks again for the help