Engine ticking noise?

Unfortunately this engine has the cylinder cancelation system which cuts off 4 cylinders when cruising, when this happens oil is cut off to the camshaft lifters which can cause the camshaft to go bad, to be sure you can remove the valve covers to check for play in the valvetrain which will help confirm the issue. Can you please shoot a quick video with your phone so I can hear the noise? That way I can tell for sure what's going on. Do you have a check engine light on? You might want to try removing the serpentine belt and start the engine for a few seconds to see if the noise is gone, this will eliminate any of the front accessories from causing the noise. Here is how to remove the valve covers.