Engine knocking sounds?

Can you get a recording of this noise? It very well could be an engine knock as that would be the likely cause of it after you found it low on oil. Does the noise get faster and louder when you raise the RPM? Does it only do it when you step on the accelerator or can you hear it if you lift the hood and the engine is at idle?

The first thing I would do is start with checking for metal in the oil.

You do this by changing the oil and draining it into a clean pan so that you can swirl it around and see the bottom of the pan. You are looking for metal flakes that will look like glitter.

Here is a guide that will help with changing the oil:

https://www.2carpros.com/articles/how-to-change-engine-oil-and-filter

I attached a number of pictures below that will help with identifying different types of metal in the oil. Clearly some are worse then others but you may have to feel the oil and rub it between your fingers to see if it feels gritty at all. It should be very smooth and oily (obviously).

If it is worth fixing that depends. Clearly it is not an extremely valuable vehicle but depending on the metal in the oil and if it needs an engine, then we can make the decision on repairing it or not. Basically you are going to weigh the cost of repair against what it is worth in good working order. If the cost of the repair is more then it is worth, then you do not fix it and you take that money and put it towards a different vehicle and sell this for as much as you can get.

If you want to get the video of the noise before you do this then that will help with making sure this is an engine knock. If this is not an engine knock then draining the oil may not be needed but I suspect that is where we are headed.

Thanks