Oscilating O2 Sensor Readings? No faults on OBD2 Scan. 2012 1.6 Duratec

[DocTrucker]

Hi All,

I'm in the middle of trying to resolve a smart charge fault, and realised I could monitor battery voltage using torque, saving me keeping the multimeter around.

Long story short while adding the two available volt reading displays to the screen and scanning the list of sensors available I notices that the reading on one of the O2 sensors seems to be swinging from ~0.2 to ~0.8V in a 5-10 second cycle. This seems odd to me, but as the only issues I have at the moment is the occasional smart charge issue and a slight hesitation I'm wondering if this is normal?

Thanks.

[DocTrucker]

   Here's a screen shot Of the oscillations. 

[iantt]

Upstream 02 sensor should oscillate and downstream of cat 02 sensor should be a fairly constant voltage. So that's normal reading.