automatic 97 gst is experiencing some knocking

[97gst ts]

okay well heres the deal my automatic 97 gst is experiencing some knocking.. not exactly sure where its coming from but what ive been told is if i blew the engine the car wouldnt start let alone drive. this one will start up and drive but it wont go anywhere over 20 mph. anyone have any clue what it is?

 

[Defiant]

Rod, main or balance shaft bearings.

Your engine is blown.