You know the scenario: You start the engine and it immediately makes a screeching sound that sends the neighborhood dogs running for the hills. It’s annoying and embarrassing, especially if the screeching continues as you drive. So, what’s the deal with that horrible sound? It’s probably related to the serpentine belt that drives a number of accessories on the engine. The belt itself could be worn, or there could be a problem with the component tasked with keeping it at the proper tension. There could be another reason for the screeching sound, but regardless, it’s best to have it inspected right away—even if the problem seems to come and go.