I need to have a bloody good think about this, my instincts tell me there is something stupid wrong.
I find when doing diagnostics, I work instinctively, other without much conscious thought, so I have difficulty putting it into words and than they still get lost in translation from Australian English to English English

If the car was sitting here in front of me I’d probably find the problem pretty quickly, alas I’m in Melbourne and your car is in Oslo.
I need to think about something else for a bit, and see if it comes to me.