Joined the failed tape club. Tape is of course, very temporary. Engineers would know this, so this was obviously an intervention by the bean counters because square and ovoid grommets are more expensive. 🤔 Either that, or there was a part shortage and they didn't want to halt the production line. There are a pair of holes back there that do have a grommet installed. So it's senseless as to why the remaining wouldn't have them.
Warning to others. Do not let any lubricant touch your vents. In the wonderful video that
@Nitelife posted, he repeated what he was told about some of the vents dry-rotting. So I applied some silicon spray as a preemptive measure. That
ruined them. 😮 Otherwise they were perfectly fine. The rubber immediately expanded. Motor oil or any other effective oil/silicon based lubricant will have the same impact. The effect is permanent. I had to order replacements and that took about a week. As a temporary workaround until replacements arrive, may be able to use plastic wrap around the inside of the vent. But that will likely get sucked/blown out. In addition, plastic retention tabs may break every time one pulls the rear bumper off. The vents must close for multiple reasons. Keeps out exhaust, insects, excess humidity, water (when moving), and sewer gasses depending on where you park. The sunroof troughs drain exits right below these vents.
Photos...
Cleaned areas with rubbing alcohol. Used metal tape to cover the holes.
Much more appropriate for this kind of application. Layers will prevent puncture/blow-out.
For the white plastic wall/screw anchors, I used silicon o-rings. (compare top to the bottom)
Went around everything with gasket maker aka RTV sealant. Did the vents once they came in as well.
If you're nit-picky, use a dark colored sealant for the two on the left as they may be visible around the tail light.
The Spec-D tail lamp grommet BTW, also has an O-Ring in there that makes them lock in there
exceptionally well. No need for sealant there in my case.
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