my front vents blow hot.....except for the right side passanger vent only and the roof vents come out cold...any advice?

 

so i hear the blower instantly start and shut off about 5-10 seconds later and repeats...it sounds a bit grindy

 

My ceiling vents are fed by the rear aux unit. Passenger should be on the main blower though.

Sounds like the bearings are gone. Should be around 50 bucks for a new one. It's mounted to the firewall under the hood on the passenger side with a few bolts.