speedometer inop using AUTO PND-A56 Ecu

[shadowbuilt915]

Hello, so I am tuning my buddy’s car and I have been chasing my tail from the beginning. The swap was done by a reputable shop, and I am discovering the parts used as I am going. The car is a …
-97 hatchback
-JDM k24a engine
-14 civic Si transmission
-PND-a56 (just found out is an auto ECU)
The original concern is inoperative Speedo. The Kpro or gauge cluster do not show VSS at all. Did the CSS rewire like the vtec academy video and still nothing. This is when I figured out that it is running an Auto ECU. I then removed pin A18 and wired it to the VSS pin on the kpro4 as recommended by hondata. Here is where it gets tricky again, I started the tune as a PND calibration and the option to select “Alternate Speed Input” under the misc parameter is greyed out. I can not select this option. I then made a PRB calibration to see if that option was selectable. It is, I was able to get VSS input on the kpro and calibrate it this way. It is also operates on the gauge cluster now. I started to tune my low fuel- 0 degree table with no success. Drivability is all over the place. I make corrections using my short term fuel trim or according to the fuel change adjustments table, and then it runs completely different A/F than it should. (reminds me of when I was using the 05-06 Type S o2 sensor on kpro) I switch back to a PND calibration and the car does perfect as far as A/F tuning with the exception of no speedometer working or live tuning on low fuel tables.
Is there a reason why the PND and PRB calibrations have these different options? Can I use a PRB calibration on this AUTO PND Ecu? What can be my solution? continue to tune the PND Calibration with no speedo or live tuning? Or possibly wire in an external wideband and run the PRB calibration on this ecu so I can have a working speedo? Please help before I spend money on a wideband and have the same outcome.

[Spunkster]

You should be able to use a PRB based calibration and once tuned properly should run as it should.

What Wideband are you using?

[shadowbuilt915]

Ok thanks for the reply , I am using the oem primary sensor. I am thinking of swapping to a new oem sensor 02-04 and see if that will help.