Why is my BMW X5 engine making a loud knocking noise?

I recently bought a used BMW X5 and I've noticed that the engine makes a loud knocking noise when I accelerate. What could be causing this and how can I fix it? Should I be worried about further damage to the engine?

It's possible that the knocking noise is caused by a faulty fuel pump. I recommend taking your BMW X5 to a trusted mechanic to have it checked and replaced if necessary.

Another possible cause could be worn out engine bearings. If this is the case, it's important to have them replaced as soon as possible to avoid any further damage to the engine.