At first I thought something was wrong with my '92 Formula, but I made a quick check of my friends' cars: an '88 GTA and an '89 Firebird, and all have the same problem: Even with the fan cranked to the max, there's very weak output; hardly enough to even feel. This makes it tough to drive in cool weather with the T-tops off.

I removed the fan motor, and improved the gasket where it meets the heater box.

I'm pretty sure that the air from the fan ALWAYS passes through the A/C evapoator, whether the A/C is on or not. Also, I believe my evaporator may have a leak...which means refrigerant oil can leak out as well....which means dust and dirt built up...which means the evaporator can become restrictive. I raised up the top half of the heater box, and the evaporator looked clean, but I sprayed some brake cleaner through it; no improvement.

Has anyone else had any luck with this? I'm wondering if there's some kind of extra-powerful fan motor I could get, or maybe a better-designed fan propeller or something.

I was thinking of installing some secondary "booster" fans near the outlets of the dash vents, but that would be a major challenge.

 

I had a weak flow of air until I put in a new ACDelco blower motor, and now I hardly ever use the highest fan speed.

You could also reinforce the ground some and clean the connectors. It can only help.

 

I had the same problem. Changed out the blower motor for a new one and didn't notice a difference at all. It's the old rat blade motors, they suck! I had thought about trying to have it rebuilt and have it rebuilt with MORE POWER, but to no avail.

Thought about having a custom fan made as well, because ours are so pathetic, but a $300.00 price tag is a bit steep right now. The guy promised me twice the power at the fan, so I will wait. For now I would say to make sure that every connection with the vent tracks is secure, maybe even tape them closed... Like you will notice the ones under your dash pad are probably pretty loose, the better the connection the more you will pick up.

James

 

I had to replace my blower motor when I first bought the car because a mouse built a nice home inside the fan. He also ate through the hood insulation and taillight wiring... the previous owner stored the car in a barn and those darn rodents got in there!