No airflow from dashboard vents
You could have some 'junk' down in the vents , i.e. dirt, pens / pencils , 22 cal brass !!!!. These items will jamb up the flappers and stop them from diverting the air to the right places. you may have to take some of them apart to get at them. See how the 'duct work 'is routed and should just have to remove couple screws or clips. On my old 4 x 4 ( '1974, I cut a hole in behind the glove box to remove items that fell in and patched it back later ( duct tape !!! ) I diagnosed the same problem in an eary *** ORD , guy used it in field to shoot Gophers, vent was full of 22 cal. brass!!! he couln't get any heat, It went to garage few times, they couldn't fix it. He was goinh to get rid of car because of it , Till I told him what problem was LOL.
'95 GMC K2500, "Bullet"Ex. cab short.4X4, 377,000kl on truck, 177,000kl on AMG engine, auto. 3:73 Ltd. slip, FSD remote mount, OPS relay,AFE air IN, Kennedy 3 1/2" OUT . '83 F250 HD3/4 " Robert The Red Ford"4x4 460, 3:55'posi . 2005 GMC : G WHIZ" crew short box, 5.3, 4:10. , '88 Bronco II 4X4, '95 141,000kl Ford F150 EX. short box, '92 "Toy" 4 runner 273000kl ,'63 Mercury 45000miles !!!! Auto insurance co. is my mistress !!!