gbynum

2008 Lariat with temperature control for heat and cool ...

I turned the heat on for the first time last night, and the fan control works but there is no air flow from the vents. I've done NO troubleshooting yet, but the cooling worked several weeks ago ... did not check last night. 30 years ago, vacuum would have moved a flap ... how do these work? Where do I start?

Thanks!

BadFish523

Could be the foam from the butterfly has come loose or the motor itself. Read this.https://www.f150forum.com/f4/stuck-v...-guide-277402/

gbynum

I'll do a little digging, thanks; what puzzles me is that it works with air conditioning ... Or DID ... that's the first thing to verify.

BadFish523

I thin if you crawl up under the drivers side you can see the actuator motor and see if it is trying to move or if it does move. Mine does it intermittently so Im pretty sure my problem is with the foam. I haven't got into mine yet but it will happen.

onthetools

my heater does not force air into the cab or little at the most. even with the fan on high. the air does enter the cab towards your feet. also little air on defrost. any suggestions on where i start to troubleshoot?

joe mcmillan

Move back up to post #2 and click on the blue txt. That is a link to another thread that tells how to troubleshoot and then make the repair.

gbynum

OP back ... I tried AC, no air, then cycled through the floor-both-defrost buttons, it started working. I'm too old, fat, and decrepit to crawl around; will have my mechanic spray some silicone spray next time it is in for service. That should minimize sticking foam without hurting it.

THANKS!

BadFish523

The foam actually starts to fall off and gets pinched between the door and the wall of the ductwork. I don't think silicone spray will help very much.

gbynum

Thanks! So foam removal is the best bet?

techrep

iTrader: (1)

Foam replacement.