How to troubleshoot BWM engine performance issues?

I have been experiencing some performance issues with my BWM engine and I'm not sure how to resolve them. Sometimes it feels sluggish and the acceleration is not as smooth as before. I've tried changing the oil and spark plugs, but it doesn't seem to improve. Any ideas on what could be causing this and how to fix it?

Firstly, check the air filter to make sure it's clean and not clogged. If it is, replace it with a new one. Also, check the fuel filter and replace if necessary. These issues can greatly affect engine performance.

Another thing to check is the spark plug wires. Over time, they can become worn or cracked which can lead to poor performance. Replace them if needed. You can also try using a higher octane fuel to see if that helps.