What is wrong with my blower, I think? on 2007 Dodge Caliber

Hello: My air conditioner was working just fine, and my heat, but over the last month the air works, either way, but it doesn't blow if I am idle and only seems to blow when I am actually on the highway (and still not as strong as it should be). It is the same for heat and airconditioning. I checked the fuses, they seem fine, what is wrong please? Thank you so much!!!!

Asked by for the 2007 Dodge Caliber
I would check the Heater blower Resistance if this goes you will have that problem.
1 more answer
That happened twice with my wife's Caliber. Both times turned out to be the cabin air filter clogged. It's located behind the glove box. The last time we removed the filter and left it out. Airflow is greatly increased.