clinging metal rattling sound near the exhaust system on startup

everytime i start my boxster from a cold start i hear a clinging metal rattling sound near the exhaust system i hear the sound only when starting but not when running, and when it heats up and i start again, its gone. my mechanic said change the oil separator, what do you think guys?

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This post was auto-generated based upon a question asked on our tech article page here: Pelican Technical Article: Boxster Air / Oil Separator Replacement - 986 / 987

[Wayne 962]

It's nearly impossible to diagnose problems like these over the Internet, but if I were to take a wild guess, I would say that there's something loose in the exhaust that is causing the rattle. Probably pretty minor, but it is annoying though. I have an exhaust rattle in my Boxster right now - I think it's one of the heat shields. When the car is cold you might want to get under there and literally poke around with your hands to see if you can feel if any of the shields or pipes are loose.

- Wayne

[derfo]

My rattle was loose Oxygen sensors, yes both of them at the back were loose on the Cats. Check it out may be an easy fix.