No air through vent? Vent Problems?

When I first get in the truck the air blows fine out of all the vents. After maybe 10min it will start to blow less and less until there is hardly any air coming out. I can hear the blower motor running. When it does this I turn it on high and it sounds like something rattling in the vents by the motor but after a minute or so on high it will start blowing out fine and I can put in on a lower fan speed and it'll work fine for a few minutes and then it'll stop blowing out vents again. Blower motor has been replaced but still have same problem. Air stays cold.

I never figured out what it was. But I did realize that when the air would stop blowing through the vents the lines and accumulator would be frozen up. I read that after a while you can get moisture in the frion which will cause it to freeze and block the air blowing in. I dont have the problem any more it just went away on its own but I did go ahead a pull a vacuum and recharge the system. So I’m not really sure what it was.

I'm gonna do this and I will let you know how it works out. Nobody else has even had a possible explanation so this is welcomed information! Thanks!

OK, I showed this link to my mechanic and he agreed that this could be a possibility, so pulled a vacuum and recharged the system. Worked fine in the shop, then a couple of miles down the road it did the same thing, so this solution did not work. I now notice that I am having the same problem with the heater, or when the AC is off and it is on outside air. The vents slowly get closed while driving. Doesn't seem to happen if the truck is just idling sitting still. The fan is running strong, but it is like all the vents are closed. Sounds like it is blocked somewhere in the dash on the passenger side.

OK, thanks. I will give this a shot!

My control panel will not switch from air to heat only blows out air vents no defrost or heat on floor?

The air doesn't blog out the dash vents. I replaced the actuator under the dash and it still doesn't blog out dash vents. Is there another actuator behind the dash or another switch or component that I am missing?

I'm not sure what blog means but if you can't feel air coming out of vents first thing that I would check is cabin air filter, if clogged with years of dirt and derby it will restrict air flow. Another thing that could be check is the blower motor.

I have been having low air flow from the dash vents. I replaced the cabin air filter a while ago, but not much difference. The fan runs fine. I suspect a problem with one of the vent doors.

Blower is running fine but no air is coming out of any of the vents.

The air flow from the vents is very weak, the fan motor sounds louder than normal as if air flow is blocked somewhere. I have changed out the filters which were very full of debris, with evidence of squirrels or mice. Fan output is stronger from the fan itself with filters removed and filter compartment left open.