My car has a mileage of about 160,000 miles. When I'm driving and decreasing the speed, I can hear an annoying squealing noise. It seems to be coming from the front of the engine. I had the serpentine belt replaced very recently, at 155,000 miles. It is a metal-like sound that occurs when I drive the car for about 20 miles upon speed decrease. The squealing disappears when I give it gas or rev the engine. I had check the following parts: pulleys, water pump, belt and idler. There are no leaks. What could be making this noise?
Hello. Thanks for writing in about your 2000 Porsche Boxster. Most of the time this is caused by the pilot bearing in the rear of the crankshaft. When it fails it will make this noise at these times. I usually pull the engine drive belt off and start of the vehicle to see if the noise goes away. If it remains, then this is the problem. If you want to have this looked at, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose the squealing noise and let you know what repairs are needed.