Hi folks, I bought a 2013 c180 recently and found that a tube connected to the exhaust is all rusty (top left in the pic below) - can anyone advice what does that tube do and whether I should be repairing/ changing it? Occasionally the exhaust pipe has some bubbling noise when the car just started or backing up slowly - is that related? I am totally new to cars, so sorry if it is a dumb question..!
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