What is this piece, and is it important?

Question

I recently started hearing a rattling noise coming from under my 2009 Kia Sedona. I jacked it up and found that a piece had completely rusted off and was just resting on top part of the exhaust system. I couldn't really see exactly where it had been originally attached. I have a few questions:

1. Is it some kind of heat shield?
2. How vital is it that I replace it?
3. Is it part of some larger assembly that would need to be replaced as a whole? Or is there a good way to reattach it without buying a replacement?

Here is where I found it (I've pulled it down somewhat here, it was originally found on top of the pipe): And here it is after I removed it:

Answer 1

To answer your questions:

1. Yes, this does appear to be a heat shield

2. In general, auto manufacturers don't include anything in the car that they don't need to: this eats into their profits. That being said, it'd be a guessing game as to whether this heat shield was added in order to improve the customer's driving experience (i.e. by reducing the amount of heat that makes it into the cabin and thus allowing the HVAC to operate properly) or if it was added in order to prevent some other component in the system from over heating. All that being said, on a scale of 1-10 with 1 being "no big deal" and 10 being "do not drive the car until it's replaced", I would place this at a 6-7. Again, it is difficult to know for sure what the heat shield's original intent is.

3. I don't believe the heat shield is part of any larger assembly. The only important thing with a heat shield is that it is sitting between heat source (the exhaust system in this case) and whatever it is trying to shield. If the heat shield is sitting directly on the heat source, it will not operate properly. That being said, you can try finding a way to mount it with zip ties (which may melt...), two-part epoxy (which will be difficult to remove, if needed in the future...), or some sort of fastener. I would probably choose the third of these: I'd drill some small pilot holes in the heat shield and somewhere unobtrusive in the vehicle, and then drive some self-tapping screws through both and call it a ady.