Knocking on the driver side of engine bay

That is a lower engine knock. Most likely a bearing has spun on the crank shaft. If you increase the RPM does it get worse?

If it gets louder and faster with higher RPM then it is a bearing. If it quiets down and then comes back it may be a wrist pin in a piston. However, I have heard a lot of engine knocks and that is what they sound like so I suspect you will need to rebuild or replace the engine.

Let me know if you have questions. Thanks

There are a number of things that cause it but the most common are low oil pressure and just a worn out engine.

Basically what creates the oil pressure in the engine is the restriction or clearance between the bearings. When this clearance gets too much then the pressure drops. When the pressure drops it is possible for things to "move" around and they start knocking.

There are other causes of low oil pressure so if the oil pressure for any reason drops, the engine can start knocking due to a bearing failure. The most common causes of low oil pressure are, oil pump failure, low oil level, lack of maintenance, or over revving/high RPM excessively.

Lastly a spun bearing is when the bearing on the crank actually spins and is no longer in the proper position so it make this noise.

Let me know if you have more questions.

Any time. We are here to help. Please let us know if you have other issues in the future. Thanks for coming to 2CarPros.