What is the most common issue with the Ford S-Max's engine?

I've been noticing some strange noises coming from my Ford S-Max's engine lately. I'm not very car-savvy, so I'm not sure what could be causing it. Does anyone know what the most common issue is with this car's engine and if I should be worried?

It could be a problem with the timing belt. I had to replace mine recently due to it making strange noises.

I've heard that some models of the Ford S-Max have faulty spark plugs. You might want to check and see if that's the case for yours.

I had a similar issue and it turned out to be an issue with the fuel injectors. It's best to get it checked out by a mechanic as soon as possible.