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lately ive been noticing some rattling and vibrations coming from the passanger seat or shift ****, and it only happens when its raining really hard or i hit a puddle, ive stumped all my friends, the dealership, and the motorsports store, the dealership blames it on my greddy sp2 exhaust, saying its the rain hitting the piping, but thats not powerful enough to make the whole car shake. the one guy at the motorsports store has a civic like mine without the exhaust and has the same problem. is anybody else having this problem, or has anybody found a way to resolve the problem?