[Goran]

Hopefully someone more knowledgeable will be along.
In the meantime I can suggest the following:

MAF - To test your MAF, log it at idle. I have attached the factory test procedure.

Lambda series 1 - intermittent, I think Ainarssems said its only the heating element going out when it says "internal resistance too high"

Lambda series 2 - they only monitor the cats, sounds like heating is dead on those, but maybe they work ok once the exhaust warms them up? They will trigger the CEL in the dash though

Fuel trim - could be from bad MAF

Here are some ElsaWin factory test procedures for MAF, Lambdas, and Brake Light switch. If you can best check for yourself if these components are operating to spec.