Q&A

it could be getting wet, therefore sliding off of the spring loaded pressure wheel or it could be that it is not tight enough. maybe you should look into tightening the alternator, ac compressor, or power steering pump. Once they are tight it shouldn't happen again. The splash guard is not a bad idea to replace.

Just had this problem, my mechanic (an honest one actually ) changed the serpentine belt, AND also tightened it, problem is fixed. I highly recommend this.
My car used to shut down, especially if it rained, once I had this done, all seems fine now...