If the engine is squealing, it is likely due to a worn belt or pulley bearing. Check the belt drive system for signs of wear, as well as the pulleys and bearings. If the belt appears to be in good condition, the pulleys and bearing should be replaced. You can hear a squealing noise coming from your car's engine compartment. When you decide to look at the belt, it seems to be in good shape. What other events could there possibly be? Following our consultation with some experts, the following is what they had to say: Many different things can cause squealing sounds. If the belt is not the issue, it is almost certainly the pulley or an alternator that has become overly slack. You will almost always need to replace the pulley or the alternator to eliminate the noise. A squealing engine is one of the most irritating sounds you will hear coming from a car. The sources of noise in the environment can range widely. How Should You Interpret Squealing Sounds Under the Hood? More often than n