I've had my 2014 (2013 FP) Lincoln for less than a week, first day noticed the A/C didn't seem to be cooling as it should. This forum has been a great place to discover some of the issues, and here is what I found in mine, and my fix-so far.
To get into the duct, poke a flat screwdriver tip into one of the three slots of the vent cover and flex it outward while gently pulling down. It will release once the tang clears. Do that again for a second tang and you can remove the vent cover. Hope you don't see this:
NO! What the - somebody needs to be schooled on what duct tape is for. It IS NOT for decorating the sides of the vent! At least now I know why the vent covers were damn-near impossible to turn. Remove all of that.
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The vents were sticking up into the duct about a half inch. That does nothing but reduce air flow. For this trick, I simply laid a Sharpie on the table and spun the vent around the tip. Then a sharp utility knife cut off the excess.
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The duct itself looks to be about 8 inches wide and 1-1/4" tall. I used an automotive mirror and tactical flashlight to inspect both directions. I saw that in several spots, CR had inserted rectangular tubing to keep the duct from being squished. I also saw where one of those was at about a 30-degree angle, again reducing air flow. I used a stick to reach it and slide it straight. After mounting the vent tube, I resealed the tube to the duct using small sections of aluminum duct tape. It takes a little longer this way, but now I KNOW the vents are sealed to the duct! I also inspected the CR-installed duct tape covering the hole in the top of the duct above every vent. I'm guessing they used a hole saw and that is where the centering drill poked through? A couple of those needed replacing. I also had one vent where the duct material did not completely cut away, but instead had broken off and "flapped" back out of the way. This was blocking half the duct right at the vent tube! If I had not stuck my hand in there to check (and the mirror), I would never have known! The final part of my fix was to cut a section of aluminum 1-1/4" angle 5-1/2" long and put it in the duct. About half of the vent holes have needed this to maintain that duct height.
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All ready for the vent cover to be snapped back on! You can see that I put a small section of duct tape on the spacer to make sure it doesn't fall over. You can also see that the duct tape does not extend very far into the tube. After putting the cover back on, it now spins as expected, and I have improved air flow! Yay!
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