What Do I Do If My Motor Is Knocking?

First stop and check that you have enough oil! Sometimes low oil can make this noise.

Is it a dull thud thud knock or is it a ping ping knock?

Thud thud knock is the sound of a part inside your engine, like a connecting rod, that has a worn bearing. This is serious, if (when) the rod breaks your engine will be destroyed.

Ping ping knock is combustion knock and can sometimes be fixed by using high octane gas.