Wideband input interferance

[gsportcars]

Hi guys,

I have tried connecting an external wideband to a customers Kpro for datalogging but I get strange wideband readings constantly. In the log it looks like voltage spikes but I have been unable to cure this issue.
I have tried two separate wideband units (Innovate LC2 and Techedge 3B1). As a side note... the Innovate wideband would not read anything at all in Kpro manager when I selected the LC2 option. I had to the select the LC1 option to get any kind of sensible readings.

But both separate wideband units gave me the same AFR readings full of spikes. From reading the wideband data on the dyno at the same time I can tell you that the correct AFR value shown in the log attached follows the lower edge of the wideband trace and not the upper edge (if that makes sense..)

The wideband units were connected to AN1. I tried with the sensor GND connected and disconnected.

File and log attached.

Many thanks.
Gav.

[Spunkster]

Where are you getting power and ground for the wideband controller?