Weak Pressure from Blower Vents

I already checked the regular culprits, so I figured I'd post in here in case someone has already had the same issue and found the fix. I'll continue to dig through posts/videos tomorrow.

2014 access cab and I had the typical blower motor resistor problem since I bought the truck. I replaced the pigtail and that fixed it for a few weeks before the new one already fried. So a few months ago, I re-replaced that as well as the blower motor resistor and bingo, I was in business.

That was during the winter, so I've basically only ran the defrost on heat until the past few days. I run hot anyway, so I never turn it on anything other than that when it's cold; the cab gets plenty warm for me.

Switched it over to the top vents and A/C and it gets cold, but there's almost no pressure coming from them. I can hear it switching from high to 3 to 2 and to low. But regardless of which it's on, I can barely feel it blowing out.

I kicked the recirculation off even though I didn't expect it to have any role (it doesn't) and I've tried it without A/C engaged, as well as turned over to heat. Same output. I switched it to high and low vents even though that's always had lower output just to rule it out -- same deal, as expected.

I pulled the cabin air filter. It's "dirty" but not really that bad. I blew it out with the compressor and I'll replace it anyway, but I went through all the above with no filter in just to check and it made no (noticeable) difference.

I know there are a lot of posts with people complaining of these trucks not being as cold as they'd like or having as good of pressure. But prior to this winter, it was always fine for me and definitely had more output/pressure than what it does now.

Has anyone ran into a similar issue?

Thanks in advance.

 

Check and make sure the blower motor is turning the correct direction, there should be an arrow on the wheel indicating the correct rotation.

 

Thank you for saying that -- I didn't replace the actual blower, but I do remember dropping it to check it visually when I did everything else and completely forgot about that. Was pretty sure I just pulled it, looked, and went straight back up, but I very well may have actually sat it down in between everything else.

I'll check that and update.

 

Sometimes the connector gets replaced and the wires get crossed.

 

Had multiple other things come up that took priority on my to-do list, but finally got around to popping off the fan today. There's no way of installing it incorrectly, so that was never a thing. I did notice, however, that the fins were pretty dirty (by my standards).

I cleaned them off (other than some minimal dirt/dust at the very ends where I couldn't really get anything to force it off). Got it reinstalled and fired it up.

Same outcome.

I can hear the fan switching speeds (I actually held it and toggles through them while I had it out to visually inspect it, too). It's doing what it's supposed to do. The heat feels hot and the A/C feels cold. There just isn't any force blowing out at the vents compared to what I've experienced previously in this vehicle.

I looked between the fan and filter when I had it pulled and there's no debris or obstructions. And like I'd said, I even ran it with no filter just to test it and the output felt the same.

I'm going to go down the youtube and google rabbit hole on this tomorrow, but if anyone had a similar experience or this sounds like something, feel free to give me your 2 cents.

On the bright side, I was able to get the bed all cleaned out today (bag of Quikrete tore yesterday) and pulled all the junk out of the cab and reorganized my tool and medical bags. So at least that happened lol.

 

Did you verify it's running the correct rotation?

 

If you switch between A/C and heat, does one feel like it has more air flow then the other one?

 

Makes no difference. Just overall decreased velocity/force.

 

So I was going to reply to this saying that it didn't make sense / that it only rotates in one direction.

Whenever I dropped it, I never disassembled anything.

However, I just stumbled onto a post in my digging and I'm pretty sure I found the issue and it's probably this.

The new harness had different colored wires and I thought I paid enough attention to wire it correctly based on the orientation. In fact, I was very careful to pay attention to that. However, I'm guessing I messed it up.

I suppose I'll be re-wiring it whenever I get a chance (again...*sigh* lol).

I'll update whenever I do. But I'm betting this is it. Glad to feel like I probably have the answer now. Just wish I didn't have to do this for a third time inside a year.

 

Can confirm this is an easy mistake to make. I pulled my hair out for a month trying to figure out why I had very little to no air flow coming from the vents. Turns out its very beneficial for the blower motor to be wired correctly .

 

Dude. I was in such a rush reading this the other day that my brain saw the cliff notes and not the actual words you typed out. Wish I wouldn't have spent all the time cleaning the stupid blower yesterday and just re-re-wired it lol.

Yeesh.

 

This makes me feel better lol. Also glad to sort this out in March before *real* Kentucky summer begins lol