[fastlife]

I have a situation with BMW that you can see in the attached videos, when it is driven cold or after a long stop, the oil temperature reaches half and then suddenly starts to fall twice until it rises to half again.
I changed the thermostat, and the mechanic says that it's fine because opening the cold water on the thermostat cools the oil, but I've own the car for 8 months and it didn't happen before, nor did changing the thermostat help, also when the first time the needle reaches halfway on middle and I put the heating on warm at 28 degrees and the fan at max, then my temperature even drops to 50 degrees, and also the rear passengers behind me are constantly blowing cold air and the air in front of me is hot.

The car is still under warranty from the seller, and he gave a warranty only for the engine and gearbox, and his mechanic insists that all it is good and in order, but as I repeat, this situation has never happened before and it started a month ago, and before that it was all OK. Can someone help me, because the car is currently back at the mechanic and I'm afraid that tomorrow they will call me again that everything is fine with the car and I don't want to accept that. The car is a 2014 n47T engine.

I connected the Bimmerlink to the car and monitored the water situation, and the old thermostat barely raised the temperature to 86 degrees, it was mostly at 75 degrees and when the temperature dropped, it dropped from 86 to 69 degrees, the new thermostat keeps it at 85 -95 degrees but also suddenly drops to 75 degrees.

Does anyone have any ideas and maybe the car has another thermostat?

The car is mapped to stage 1 with egr off and dpf is left active for regeneration..

Thank you very much

[fastlife]

https://youtu.be/Ik93CwgEDz8

[fastlife]

https://youtube.com/shorts/15wgpm1Zjhw?feature=share

[fastlife]

[fastlife]

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