OK, tried switching from warm to cold. Not sure I heard the blend door but the fan did sound differet and definetly colder air. Guess I'll try flushing in the A.M. Any thoughts would be greatly appreciated. On a side note, possibly unrelated, about a week ago, while standing outside the truck at idle I noticed the a/c compressor cycling off and on. Since I haven't used the a/c in months I thought it odd, how about y'all?

 

Compressor will run if you have your vents set on any flavor of defrost.

 

HeyYou, Surely I've heard it before, just paid no attention.

FWIW, I already have 1 splice, I'll make another to isolate the heater core and connect to a garden hose to try to flush. If that doesn't work, I reckon I'm going to see what it looks like without a dash. I'm hoping one of y'all might have some pointers, tips, or other insights