I have 98 Dodge Ram 1500 4X4. The air from my HVAC blows 95% of the air out of the floor vents all the time, no matter if the setting is defrost, vent, or heat. A little air comes out of the defrost and dash vents. I checked under the dash and when I change from defrost to heat to vent I can hear and see the vacuum accuated linkages move, but the air still mostly blows out of the floor vents. The temperature of the AC or heat is fine. I have not seen this exact problem on other posts here, unlike the other posts, this problem does not change if I accelerate and my cruise control works fine. Thanks in advance for any help you can offer.

 

Had the same problem, drove me crazy for one summer, after alotta looking around and surfing i found out that the vacuum canister behind the abs computer had came undone from the plastic stick that moves the flap back and forth, connected back with the help of a small friend being 6'4" 250 hard to get under there and fit my hand in there, and wrapped it with tape so it doesn't come back off, it may help looking to see if thats the problem. Or ur good to go if u like a cold right foot lol

 

Thanks for the tip! Not only is it a pain in the summer, but it also keeps the defrosters from doing their job in the winter. I'll take a look at it and let you know.

 

Yes please let me know if u had the same problem. Didn't know bout it messing up the defrost living on Hilton Head, SC no chance to use it.

 

I have a 99 dodge intrepid and my heat only blows hot when I acelrate. What could be the problem I'm having