Buick Riviera Forum : “Heating System”

I have the same problem with mine.  The blower fan works fine.  I have'nt fixed the problem yet due to the fact of the heated seats.  I think it could be a somewhat clogged heater core, or something preventing the radiator fluid to in or out of the heater core in the hoses that lead to it.  Or it could be something as easy as a thermostat, which is a 7 dollar part.