Why is the turbo in my BMW 5 Series making a strange noise?

I've noticed that whenever I accelerate, there is a loud whistling noise coming from the engine. Is this something I should be concerned about? What could be causing it?

It's possible that the turbocharger could be malfunctioning or damaged. It's important to have it checked by a qualified mechanic as soon as possible to prevent further damage.

Have you recently had any modifications done to your car? Aftermarket parts or modifications can sometimes cause issues with the turbocharger.

Another possible cause could be a leak in the intercooler pipes. This could be causing the air to leak out and create the whistling noise you're hearing.