How can I improve the performance of my Ford S-Max's engine?

I have noticed that my Ford S-Max's engine is not performing as well as it used to. Is there anything I can do to improve its performance without spending a lot of money?

One thing you can do is regularly change the oil and filter in your car. This will help keep the engine running smoothly and at optimal performance.

You may also want to consider using a fuel additive to clean any build-up in the engine and improve its performance. Just make sure to choose one that is recommended for your specific model.

Another option is to have a professional mechanic check and replace any worn out spark plugs or other components that can affect engine performance.