When should I replace my BMW 3 Series' spark plugs?

I've been noticing some strange engine noises and a decrease in performance. I'm wondering if it's time to replace my spark plugs.

It's recommended to replace your spark plugs every 60,000 miles or 6 years, whichever comes first. However, if you're experiencing issues such as strange noises and decreased performance, it's best to get them replaced sooner.

You may also want to consider the quality of the spark plugs you're using. OEM spark plugs are specifically designed for your BMW 3 Series and may provide better performance and longevity compared to aftermarket options.

Another factor to consider is your driving habits. If you frequently drive in stop-and-go city traffic, your spark plugs may wear out sooner due to increased combustion cycles. In this case, it's best to monitor the condition of your spark plugs more frequently and replace them if necessary.