Why is my Vauxhall Insignia's engine making a knocking noise?

I've noticed a knocking noise when I start the engine and it continues while driving. What could be causing this and how can I fix it?

There are a few potential reasons for this knocking noise. It could be due to low oil levels or old, dirty oil. Check and change the oil as needed. It could also be a sign of worn engine components such as bearings or pistons. If this is the case, it's best to take your car to a mechanic for a proper diagnosis and repair.

Another possible cause could be spark knock, also known as pre-ignition. This happens when the air and fuel mixture in the engine ignites before the spark plug spark, resulting in a knocking noise. To prevent this, use high-quality fuel and avoid excessive engine load or high speeds.

One more thing to check is the engine's timing. A misaligned or damaged timing belt could cause a knocking noise. If the timing is off, it's important to get it fixed as soon as possible to avoid further damage to the engine.