Hello. I was wondering if anyone here might possibly know what this noise is coming from my engine? It has always made it but has gotten progressively worse over time. I will also apologize now if I have posted this in the incorrect place. I have uploaded it to youtube: http://youtu.be/9xhku6xchwk I additionally thank you for any replies or help.

Edit: The engine was not to operating temperature.

 

That actually sounds like the beginning sound of rod knock. I would compression test to see. You can also pull each spark plug wire one at a time while the engine is running and see if the knocking goes away after one of them is removed which will tell you which cylinder, provided the knock goes away after pulling a particular spark plug wire.

Keep in mind that it is possible to blow your coil from doing that so just keep that in mind.

 

I forgot to mention that the noise is under the valve cover. Also, if it is the beginning sound of a rod knock, how much longer would you say the engine has left?