Pontiac Repair: cabin ventilation, radator, cabin filter

Question
My wife's 97 grand prix has a reduced air flow from the heater and the a/c. The temperature is correct for the relative unit but the flow is less than half of what it was earlier this summer. The research i have done indicates cabin filters were not in use in 97. Thank you for your assistance.

Answer
Hey Pete:

The issue here is a plugged up evapoorator core. The car does not have a cabin filter your right If it did you don't have this issue. the outside air /dir/pollen has dotten stuck to the evaporator core and the fins where the air flows are plugged up. it's like the fins in a radator under the hood of the car same idea. if it had a cabin filter from the factory that filter would have caought the dirt before it got caught in the core. How  to fix it... Good question There is no way to actaully see it you can take the cowl off that is under the windshiled where the wiper blades park and you can can see into the air box where the core it. You can only see a small protion of it if you look in and towards the drivers side. I don't really recomend doing this BUT a small steady spray from a garden hose may be enough to wash the crud off the core. If you try this take the blower motor out and the resistor for the core out and put some towels down where those are in the heater dox on the passenger side of the car the water will leak out on the cars floor... This will make a big mess!!!!! make sure the water is running out of the heater box and onto the ground or else you will flood out the floor in the car. there is a drain in the bottom of the box and if that gets plugged up it will back up into the car again this will make a mess... The correct way to fix it is to take the heater box out of the car and diasassemble the box and clean it out that way.. BUT your looking at a lot of labor and a BIG job to get it out of the car. maybe 8 or 8 hours of labor at what ever a shops rate is so it's an expensive repair.. when you are done trying to spray the dirt out. put the blower and resitor back in and start the car up and run the a/c with the temp dial about in the middle and let it run for a while to dry out the heater box. good luck and Like I said thi is not an "aproved" repair method.