135k miles on mine, not a single problem at all EXCEPT for one of the few pieces of the car that are GM, that would be the blower motor resistor that finally crapped out. Replaced it this week and now I have a fully functioning fan unit.
When i replaced my rear drums they looked like every other rear drum setup i've ever seen and the driving in reverse and pulling the e-brake was always the method to tighten them up so i would "assume" that's the same practice for the Vibe, but don't know for sure.
I had/have the same problem. When fan works it works fine at any speed, when it doesn't i can hear the AC comp kick on but the fan does not.My fix: just to the right of the fan control unit on the side of the console, give it a good swift firm hit with the palm of your right rand, Instant fix. It's ...