Re: Cruise Control and Hydroplaning
From: Douglas M.

I'm sure real experts will chime in, but this sounds like hokum.

Cruise control will try to regulate the speed based on the feedback from a tachometer downstream of the transmission (not the tach that shows engine speed). If a tire is spinning on the wet surface, the tire is no longer providing traction, hence it is no longer affecting the speed of the car. When the tire starts to spin on the water, without the friction of the road, it will be suddenly be going faster than the car and the cruise control will REDUCE the speed command.

Once the tire regains grip, the speed feedback will be again match the speed of the car. At this point, the car will be going slower than the speed setpoint and the cruise control will increase the speed command until the car is back to the setpoint. So, as the car hits the pavement again, the car will automatically speed up, but only to the speed that you set your cruise control to regulate, no faster. It may surprise you because it goes from slowing down as you slide to accelerating (temporarily) as soon as you hit the pavement.