I have searched and searched, but not found anything like this. The car is a 97 c36. it comes up to normal operating temperature, and using the gauge and climate control head unit, stabilizes around 82-84 deg. Normal. But then, the fan clutch engages, and as I drive, the engine temp. drops to 70deg or so and stays there until I am in stop and go traffic again whereupon it warms up again. The fan clutch engages and I get the associated air movement noise (loud). I wouldn't have thought with such an engine temp. and an ambient temp of only +2C, that the fan clutch would engage at all. Any experience/thoughts?