In warming my truck up the temp. gauge shows 190-200 as it usually does but all of a sudden the fan is blowing cold air until I get in and drive the truck. Then the air temp warms up to normal temps.
Any ideas what is going on with the heating? In the mornings while it's sitting there idle the air will not heat up. The temp gauge seems to be fine and showing that the air should be warm. I have to get in it and drive it then the air heats up.
Sounds like the blend door is sticking possibly from the cold and as the interior warms up the door opens. is the truck exposed to a lot of dust in the summer? may need to blow out duct system.
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