I have noticed an intermittent vibrating or humming noise from the engine over the last couple of weeks this summer. I will not hear it during my first drive of the day or if the car has been parked for several hours. If I park briefly and then restart the engine, the noise will be present. It will seem to stop briefly if I accelerate or jiggle with the A/C-heating fan/temp controls, but will come back with no real consistency until I'm parked for the night. I suspect something is getting too hot but I have no idea what to be suspect of. Any ideas?
