Hi Wendy, I have 2017 Tiguan with the same issue. On my first visit, the dealer said they weren't able to reproduce it, so I recorded it and took it back. They said it was the fuel line that was vibrating so they replaced the clips. It did make a difference, but it still makes the noise from time to time (less frequently, and not as loud). I only had it fixed last week. I need to take it back again.
Here's a video of mine (before the repair). Sound familiar?
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