When I come to a stop after a half-hour or more drive, particularly at freeway speeds, i hear a squeaking noise at idle. Slightly raising the engine RPM makes the noise stop. I thought the noise was coming from the belt line somewhere, but the noise is actually quieter when leaning over the top of the engine. The squeaking noise goes away after several minutes at idle, particularly if I raise the hood (which I’ve done to try finding the noise source).
If I let the engine warm up from cold at idle without driving, the noise doesn’t occur. It only occurs when the car is driven.
I’m thinking that the noise is coming from one of the exhaust joints that get really hot from driving the car. One of the joints is moving about slightly when the engine is vibrating at idle and creating some metal-to-metal rub. The joints don’t get as hot when the engine is warmed up at idle.
Anybody else encountered this? Any other ideas for a cause?