My 2002 grand prix a/c is only throwing out cold air on passenger side but not the driver side..what could be the problem?

Look for a loose to broken air hose for the drivers side damper motor.

Possible blend door

If you have warm air on one side and cool on the other, you've a situation with the vent flaps. But to backflush the core, take both hoses off the core and run a garden hose to the outlet side going towards the water pump. This will flush it.

ether the blend door actuator is bad or the climate control module is failing. most likely the blend door actuator. would have to pull most of the under dash out to get to it to replace it. not fun at all.

no idea, but you figure it out, be sure to put it on here. My wife's 2002 GP does the same thing. Raise the passenger side controller then slam it down, it will stay cool till the next stop sign. Then do it again. Its gotten us by for the last few months since its happened.

sounds like heater box diverter stuck close is it manul switched or when your turn switch you hear a wistle **** sound could be a purdger gone//// good place to start looking

must be low on freon

climate unit is bad

I'm going to assume the fan louvers (that direct air from wind shield head to feet ect) are electronically controlled. If that is the case, then a motor may have died. You only have one AC system for the vehicle, so if its cold on one side, then the fault lies within the air ducting system. Maybe a mouse built a nest in there and is blocking air flow?

Check the ac filter, it might be dirty and thats why it is not blowing out enought cold air. The filter is located under the wiper cover but behind the firewall on the passengers side. You access this by lifting the hood and removing the rubber type gasket that holds both together, right on top of the blower unit.