Odd Blower issue

:
Mazda 5
The fan in our 2013 Mazda5 seems to have some issues. Occasionally it won't work on start up but will kick in after a while then be fine for weeks until it happens again. I am hoping (banking on actually) that when it comes time that I NEED to deal with it, it's just the resistor. From what I've seen of a YouTube video of it being replaced, I think I could handle fixing myself. The prospect of having to take it in and have the dash taken apart just to get at the motor scares me to death - actually the though of what it'll cost.

But there seems to be another issue which I can't really explain. Sometimes the AC output (seemingly a fan issue as well) is pretty paltry, but, If I take a hard left turn something seems to shift and the output surges and seems to stay that way. Seriously, is the turn really shifting something? Any ideas on that one?
 
Back