Suggest to perform diagnose at work shop, usually the keypoints of diagnose are:
1. Check if there is damage or crack on the exhaust manifold.
2. Check the exhuast pipe and catalytic converter if it is leaking or damaged.
3. Check the silencer if it is leaking or damaged.
4. Check if there is leakage occur at the gasket between silencer and exhaust pipe, is there any damage at the exhaust pipe and silencer rubber holder washer.
5. Tighten the connecting bolt between engine, exhaust pipe and silencer.