Pontiac Repair: HVAC, 3800 engine, blower motor

Question
I have a 2003 grand prix with a 3800 engine.the heat switches from defrost to floor to front vents ok and from hot to cold ok but as I turn the fan up it may go up a little or it sometimes goes all the way up. Not consistent. seldom goes all the way to high but sometimes. If AC is on but fan will only barely blow and I switch to Max AC, it goes off. ???

Answer
Hi Troy:
Does this have Manual HVAC (duals) of Auto HVAC (digital diplay) If this has manual HVAc chances are you have an issue with the blower desistor block. If it has AUTO HVAC it could be either a blower motor control mopdule or a power issue. when the blower quts does anything else stop working? PRNDL lights on the dash or does the dash quit working altogether or the rado power windows etc???