Very weak air from side vents

[evilnickwong]

My AC is pretty strong from the center vents, but it's really weak from both the side vents. Even on speed 4, it's still noticeably weaker compared to the centers.

The only thing I can think of is that the air ducting to the vents (under the dash) must be broken/not sealed somewhere?

[Ceeker]

that is quite possible, also check the flaps in behind the vents to make sure they are opening and closing fully. you can pull those out with a bit of force. Turn the actual vent all the way down. Get a small screwdriver and lodge it up top in behind the actual vent and give it a good tug forward. it will release it and then turn the vent up to pull it out. You'll see how it works to get it out once out. Then you'll expose the flaps and check.

[evilnickwong]

Thanks for the feedback. I've checked the flaps behind the vents before, they definitely open fully.
I'm guessing checking the ducts will be a dashboard out job? :(