oil temp sensor via can not reading correct

[Yves]

I have an GM coolant temperature sensor that I use as an oil temp sensor. This work fine until recently. It shows erratic behavior even at start up. The way it behaves has lots of things in common with the WB sensor that are also connected through the IOX. Like when it starts up, it shows a certain high value, then it goes somewhat lower and then it goes to -13°F or something. It's kinda the inverse of an AFR gauge when starting up;

No matter what I tried seems to solve this.

I checked my wiring and my IOX and my sensor and cannot seem to find anything wrong. The sensor outputs a stable voltage.

Attached is an msq.