not much fan air blowing...

93 S10 Blazer 4X4 4.3L Vortec 4 door auto power everything...

Any ideas on what to check for fan air not blowing out like it should. Fan on high and really doesn't blow very good. Blend door changes settings like it should, can hear it move when changing settings. Pulled out fan in engine compartment, looked like a fan to me. Doesn't seem to be any obstructions, haven't had any rodent problems.

Just wondered if anyone has any tricks to try.

Can you hear a difference in the blower speed for all 4 speeds?

Yes, it has the 3 different speeds you can clearly hear...

Should be 4 speeds, which one are you missing?

Sorry,
Low is actually on too. There are different speeds for every position on there. Thinking maybe fan is not putting out as much as it should anymore.

All HVAC air flow passes through the evaporator. If the fins are clogged, air flow will be reduced in all mode switch and temperature positions. It's not a fun job to inspect the evaporator, but that would be the most likely place to look for a restriction.

Thanks Master, will look into that!

I had an 89 S-10 and had to replace the blower motor a couple of times. I'll give you a few pointers that I learned the hard way.

The original motor didn't seem to work at all. When I pulled it out, I found that the motor was the wrong motor. It LOOKED right, but it spun backwards. It turned out to be the wrong motor the previous owner got out of a junk yard. The lesson here is that there is an arrow of rotation on the squirrel cage of the fan. Make sure it is rotating the right way. I replaced the motor with a motor from the junk yard and wasted my money. It ran, but it didn't really blow the air through the vents and into the cab too well. I bought a brand new motor in the box from Autozone and it made all the difference. These fans do go bad. Some will start to squeek, some just quit. If you find that the coils are clean, you might need to invest in a new blower motor. Also, check the fan housing for obstructions. I remember finding napkins inside of the housing when I opened mine up to replace the fan.