Why is my Vauxhall Movano's engine making a loud knocking sound?

I recently purchased a used Vauxhall Movano and I noticed that the engine is making a loud knocking sound when I accelerate. What could be the cause of this and how can I fix it?

The loud knocking sound could be caused by an issue with the engine's internal components, such as the pistons or connecting rods. It is best to take your vehicle to a mechanic for a thorough inspection and proper diagnosis.

Another possible cause could be a lack of lubrication, which can also lead to engine knocking. Make sure to check your oil levels and change it regularly as recommended by your vehicle's manual.

If the knocking sound is more pronounced during cold starts, it could be an indication of worn out engine bearings. In this case, it is important to have them replaced as soon as possible to prevent further damages to your engine.