Be sure to check the fuse in the top of the overvoltage relay. It is behind the battery in the top of a relay (the one with the red top).. Most of the time it is this. What year is your Mercedes??

I have never seen a fautly cold start valve on a Mercedes.

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Benzmac:
Donnie Drummonds
1992 500E (very soon I hope
1981 280GE SWB
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