I believe someone in the past had similar issues, and cured it by replacing the coolant overflow reservoir cap. Cheap place to start, anyway.
Another thread at Overheating! Am I missing something?
found the problem to be an intermittent fault in fuse D in the fuse box, for what it is worth. Good luck.
2003 Firemist Red/grey leather SL 500
2015 Palladium Silver/black mbtex GLK 350
1987 Smoke Silver/burgundy mbtex 300E Sportline (SOLD)
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