Ok you misunderstand what I'm saying about pressure.

The reason that the cooling system gets so worn out is because BMW went with a higher temperature thermostat and to ALLOW that temperature increase they had to increase pressure. You seem to think it's the temperature causing wear and tear (it's not, hence expansion tanks popping) and running a lower thermostat cures it all. With a lower temperature you do NOT need to run that higher pressure so reducing pressure will also reduce stress on hoses, tanks and header plate/tube welds. I used to build/rebuild radiators for a industrial applications about 35 years ago.

I do know how a thermostat works but since the original BMW thermostat is partially controlled electrically to help manage fuel economy and so forth it's not just straightforward like a thermostat that is just a bi-metal valve AKA bellville spring.

Does your new lower temp thermostat still have an electrical connection? If it doesn't then there is how you can fix it by providing the circuit with whatever data it's expecting.

Also you might want to understand that just because you asked a question no one here has to answer you and your (Wow really!?!) post set the tone, plus we each have our own way to troubleshoot or flowchart things, after posting it's advisable to wait since we are from all over the world and timezone issues can delay responses. Especially when being asked by someone with only 15 posts, a free account who is such an expert in BMW OEM software.

Foxwell does all the same things as ista-d and can even code some modules like ista-p though for doing coding it's definitely not as good.


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