AGREED, (Although this is from my E39, i think i can help a bit) when my thermo was just replaced, it got stuck closed a few times, but then never happened again. (no coolant loss either) Keep in mind it was a new part, I wouldn't let something like this go unchecked with an aged one.

I had almost the same symptoms you are going through.

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~The Family Cars~

1997 BMW 540i [Jet Black / Black] [None ]
2001 BMW X5 4.4i [Jet Black / Black] [Sport]
2003 BMW 540i [Sterling Gray / Gray] [Msport] [Shades] [Folding seats] [DSP] [Aux] [ICE V5]
2008 BMW 550i [Jet Black / Black] [Sport] [Paddles] [Comfort Access] [IPOD] [Shades] [Nav] [PDC]
A 5'er that was almost too good too be true.


C~Certain
P~Problems
O~Overlooked