I have a 2k GLE and I am hearing a "different" sound during a cold start than before. The sound happens always when the ACC is on "auto" and the car is cold starting. It sounds like a squealing belt. The sound happens some of the time when the car is cold started and the ACC is on "econ." When I first started having this sound I took the car in to get the belts changed. It helped a little bit, but now the sound is back and louder than before.

I am thinking it is coming from the belt that drives the AC compressor, since it's always on when the ACC is set to "auto". But that doesn't necessarily explain why I am getting the sound when the ACC is on "econ," unless the belt is still running without the compressor on. So is it something where I need to have the belt lubricated? I know there is a special belt dressing that can help with squealing. Does anyone have experience with this and can help me out? I'd appreciate it.

Thank you.

 

I think STP makes the Belt dressing.. I've used for a belt on my riding mower, and it did help. Never tried it on a car though.