Something knocking?

yea for those who own engines that knockslike a mofo you need new bearings for ur rods or its just a bent rod in the cams :P its the only real reason this would happen in any car
but hey thats as easy as taking the cam covers off lol and timing belt...

Could also be the water pump if the knocking is slight.

Or a loose flexplate, or torque converter bolts

Or your A/C compressor clutch bearings