For a couple of months now, I have known of an under panel that I saw hanging down on the passenger side behind the front wheel. Turns out, the under panel is part of the wheel well liner!? That I hadn't noticed before today. That will be an expensive part and somewhat involved to pull the damaged one out and put a new one in. What to do?
I jacked the car up so I could get in under there a bit further and take a look. I compared both sides. Turns out, the right side is missing a plastic rivet. This is what that looks like on the driver's side:
Apparently the missing rivet allowed the panel to sag and something snagged the forward edge, which put pressure on the trailing edge mount and tore it out. (I don't recall any "incident"; but we usually don't in these matters.) Anyway, I rounded up some hardware and even managed to find a stubby slotted screwdriver (necessary to keep the slotted bolt from turning as I ratcheted on the nut over the washer: this three piece fix replaced the missing plastic rivet.
This was a bitch. I had to find the slot in the bolt head by feel alone, match the stubby screwdriver to the slot and fit it and then hold the screwdriver in place with my right fingers against the frame above: this was all by reaching around the inner edge of the under panel. And then reach across my supine body with my left hand and find the nut and put the ratchet on it and start cranking: this was all done in the narrow gap provided by the jack, which was at the same time directly in my way!? I had to work my way in between the jack and the tire. Exhausting to both body and patience. But I persevered and it is tight.
The easiest repair was the telltale hanging under panel trailing edge, where the original hardware was still attached to the frame, including the ripped out section of under panel (which you can see in the pic above). I just left that. The bolt has a conveniently long end (as you can see in the third pic, despite the angle being almost directly below it; if you lie down right even with the rear of your front tire and gawk up under there, you can see how long the bolt is), which I made full use of by slipping a washer over it and tightening down a second nut on top.
I feel so clever and industrious! No new under panel/wheel well liner required; no trip to the service center. Yay! And everything is back up tight against the chassis where it belongs. Man!
(Yeah, I know, "before" pics would have been so much more useful than blather. Too late now!

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