It can perform properly above freezing temperatures and then freeze at lower temperatures. That can happen if it is clogged up with condensate that has emulsified into a paste. Getting the engine hot and burning off the moisture is a good thing, as it womt add more condensatemto the CCV, but it does nothing for the gunk that is already in the CCV, which doesn't get hot in normal operation.

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2007 X3 3.0si, 6 MT, Premium, White

Retired:
2008 535i, 6 MT, M Sport, Premium, Space Grey
2003 X5 3.0 Steptronic, Premium, Titanium Silver
2002 325xi 5 MT, Steel Grey
2004 Z4 3.0 Premium, Sport, SMG, Maldives Blue