How to troubleshoot a malfunctioning engine in a BWM car?

My BWM car's engine seems to be malfunctioning. It's making strange noises and there's a lack of power. What could be the possible causes and how can I troubleshoot the issue?

The first thing you should do is to check the engine oil level. Low oil level can contribute to engine noises and lack of performance. If the level is low, top it up and see if it makes a difference. If not, then you should take your car to a professional mechanic for further diagnosis.