help - broken temperature gauges

[jakob 2.8]

So recently my z3 2.8, with the m52tu, has started to do something weird. As I drive the car, it never seems to fully reach operating temperature, and the temperature swings between all the way cold and almost fully warmed. And so to the weird thing, when I plugged the obd2 scanner to it and viewed the temperatures showed 85 celsius (185.f) for radiator port, 120 celsius (245.f) and 155 C (311.f) engine oil, the latter one seeming impossible. I have checked the oil as it was overfilled, it was a nice brownish yellow color, and I topped off the coolant with some water. I believe the oil temp sensor might be broken, but can't see how this is related to the car seemingly thinking its not reaching operating temps.

This was all measured after a slow in-city commute of about 15 miles.

 

[Nodzed]

Sorry wrong post just ignore me

 

[NZ00Z3]

By "fully warmed" are you saying that the needle is at the 12 o'clock position?

I had a faulty thermostat that had failed open. The car would slowly get to normal temp (needle at 12 o'clock) when driving around town, but the needle would drop half way towards cold when on the open road. Is this your symptoms?