i have got an 2002 ec 300 and it has a little leak. It is leaking from where the exhaust exits the engine port, it looks spring loaded but as a bit of play/movement in it. It may need a new gasket or gromet.
Obviously check nothing is broken. Typically the pipes don't fit exactly and pull one of the gasket o-rings out when the exhaust is put on. I have found the o-rings so difficult to fit correctly I stopped bothering and use high temp Silicon RTV to seal the joint instead.