[hotrod]

Interesting observation.
Here where I live I simply shut the WI off at temps below 50 deg F or so.

Not sure what the temperature rating is for your switch. You might be able to chase that down from the manufacture if you have the part number. It could be just a case of lubricant in the switch getting stiff at cold temps.

One solution used in electronic equipment would be to build a small "oven" for the pressure switch.

Build a small sheet metal enclosure (possibly a metal circuit box) around the switch and put a small 12v lamp inside the box. Find a temperature switch that would close at cold temps and put it in the box as well. If the temp is low, the thermal switch closes, and turns on the small 12 v lamp (only when the ignition is on! ) , the heat from the lamp warms the switch until the thermal switch shuts off as it warms up.

You could also make the 12v lamp a manual heater with a simple switch.


You could also substitute a common resistor for the lamp.

Larry