A/C and Heat Air Volume at the Vents Fix

[JBDive]

I have had a heck of a time with low air movement from the vents when the A/C was on re-circulating air and I suspect when on heat as well. Everyone wanted to blame various mechanical issues, many of which could cost hundreds of dollars but I fixed my problem in 10 mins and no tools.

In my search for answers I found the following site:
"How to fix Jeep Liberty blower motor (resistor) – with pictures"

A few steps down in this post there is an image of the blogger pulling the wiring harness but I noticed something in that image, what looked to be a filter far up in the dash behind the glove box.

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So I drop the glove box as I have done a number of times before, got out the high power flashlight and low and behold way back up in there is a filter or mesh vent if you like and it is covered in lint, dust and crud. A minute or two with the shop vac and everything was as clean as when it was new so now time to test.

I start the car with the A/C in the outside air position and fan on #3. Vent pressure is good as expected so as I watch the mesh filter I switch to re-circulating and right there behind the mesh is a blend door and I watch it open up wide and as it does there is no change in the air pressure coming out the vents.

Problem Solved!

If you have never cleaned this mesh filter I highly recommend you do so. Why this is not mentioned in any owners manual, service manual or website astounds me. Do it now!

 

[ghostrider]

I cleaned mine off when I replaced the resistor recently and thought I noticed a difference in air flow. Good to know I was correct

 

[profdlp]

I need to check mine. Been a while.

 

[JBDive]

Granted my Liberty is an 02 and that's a lot of years of sucking air but I was surprised how thick it was on there considering how far up in the dash it is. It shouldn't be sucking a ton of carpet fibers and generally I don't have the windows down except for a few weeks in the spring and summer so outside dust is limited.

So to anyone that has never pulled the glove box down and cleaned this off, do it now. Why this isn't mentioned anywhere by Jeep means a lot of owners probably went in for service for A/C, paid some inflated price for parts replacement and then the mechanic just took a vacuum to the filter.