2014 CTS V-Sport Premium, 1983 Mercedes 300SD (project car), 1997 Jeep XJ
I have a whistling noise that corresponds to RPM. Any thoughts on what I'm looking at here? Vacuum leak? I have an aftermarket carmax warranty with a $250 deductible. So depending on how cheap/easy it is to diagnose/fix I may or may not just bring it to the dealership. But obviously it would be good to have an idea of what's wrong before bringing it in.