Hello, welcome and thanks for asking your question. My name is*****'m a Certified Auto Technician with 28+ years experience. I will do my best to assist you. please keep in mind that I may need to ask questions of you before I can answer. When you reply please feel free to add as much detailed information as possible pertaining to your concern.
This accordion piece is not actually a seal but since it is broken inside the track, I suspect that it has migrated into the sunroof drains and has caused blockage of the drains causing the sunroof to leak.
There are 4 drain tubes, one at each corner of the sunroof tracks. Clean these troughs and drain inlets to allow the water to properly drain and all should be well...
Keep me posted and let me know if you have any additional questions...
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