I have an '07 Pontiac Vibe. I’ve been noticing that the big fan infront of the engine runs high and very loudly when I have the defroster fans on in the cab of the car. Is this normal? It goes back to normal when I change the cab fans to anything else. (towards the floor, etc) I don’t want this to turn into something major.
It may be normal under the consideration that many cars kick the fans on high when the ac is on, and many cars kick in the ac on defrost setting. Check out one at a used car lot and see if it does the same thing.
This is normal. My '05 does the same thing. The front window dehumidifier setting uses outside air and the A/C system to clear your windshield. What you hear is the fan kicking into high because of the A/C system running.
Got me again. Better late than never I guess but Barky answered it a couple years ago.