How to improve the performance of my Audi A4 engine?

My Audi A4 seems to have been experiencing some performance issues lately. The engine feels sluggish and there is a noticeable decrease in power. What could be the possible causes of this problem and what steps can I take to improve the performance of my engine?

First, make sure your engine oil is of the correct grade and has been changed recently. Low quality or old engine oil can affect the performance of your engine. Next, check if your air filter is clogged or dirty as this can also lead to a decrease in engine power. You can also consider using a fuel system cleaner to remove any buildup in your fuel lines. Lastly, have a mechanic check your spark plugs and ignition system as faulty spark plugs can also contribute to poor engine performance.