I am getting an odd smell when from the vents when I am pulling in outside air. Not like a dead mouse or anything, just like a stale odor. Not overpowering, but enough to notice. No smell when the recirc is enabled. My truck was sitting in my driveway for the past 3 months while I was recovering from a broken leg. I just changed the cabin filter, but no help. Where does the outside air get pulled in? Base of the windshield? I want to check it to see if there is any debris, etc that is causing the smell. Thx.

 

Yes, it pulls from the cowl vent underneath the wipers. I lived down south for many years. We would regularly have this problem if we left the vehicle and did not switch it from recirculate. Since then, about 20 years ago, I always switch to vent before turning your vehicle off. Doing this allows, the fresh air to circulate into the housing, eliminating any chance of the buildup of mold and funky smells. Be sure to check your drain line. Not sure where you’re located but in the warmer states within 10 minutes you should see a condensation puddle begin underneath the truck.

 

I had that issue in my VW Caribe and fixed it by going to a self-service car wash and blasted the leaves and debris out. I don't know that's possible with the F-150.

 

problem with that is is you get too much water in that cowl too quickly, and it will overflow into the HVAC housing