Because of colder weather, your thermostats was close and oil was denser .

 

Yes this is a good point. It was frosty the other morning when I set off. This is the first winter I am using the car. Today the pressure came down slightly but still high.
The coolant temperature is showing N which I have read is not correct.

Thoughts?

 

All my V12 cars had the oil pressure gauge almost at the top peg, when cold (1 or 2C), and soon settled to above 1/2 gauge at 1200RPM. I would not get stressed about the pressure.

Temp, ummm, if its rising above what it was, and has been sitting more than using, the radiator is possible starting to get to "service" time.

Many other things come into play:
Stats
Fan hub
Pressure cap
etc etc.

 

So now water can go through plastic? Does it turn into wine?

 

How can running at 'Normal' not be correct?

 

I did not say that. I said water VAPOR can pas through plastic. Its a known scientific principle and the reason Plastic Encapsulated Integrated Circuits or PEMS for Plastics Encapsulated Microcircuits) are not allowed to be used in high reliability products such as artificial hearts or spacecrafts or satellites,The water vapor passes through the plastic SLOWLY but it gets through and causes the wire bonds inside the package that make connections to the IC die to corrode and fail.

I actually got the shelf life issue from a motor oil website so you might not believe it but the science is real!

VAriicle on Water vapour and your packaging ? the truth behind the myths

https://www.intertek.com/polymers/barrier-properties/

https://www.pnnl.gov/main/publicatio...PNNL-26070.pdf

https://www.bellperformance.com/blog...oil-shelf-life

 

Whatever you are smoking I want some.

https://mechanics.stackexchange.com/...old-and-go-bad

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