blower problem

I am hoping someone can help me. I have a 1999 Blazer that has been good to me so far. The other week I noticed when I have my control knob turned to heat for the floor it still blows out my defrosters and not the floor. Is there any simple fix for this problem or are we looking at an extremely expensive repair bill. My father has helped me in the past but is rather clueless on this. I phoned a car dealer and they are saying my repair bill would be $500+. We are thinking of trading it in for fear of other things going wrong. It has 84,000 miles currently on it. I would put up with cold feet but it is already getting old as it is still very cold out. Please help. Thanks.

Check all vacuum lines in the engine bay and make sure the vacuum line is connected to the vacuum ball in the engine bay.

If you don't see any loose vacuum lines in the engine compartment, take a listen under the dash near the glove box. That's where the vacuum lines run into the vehicle to the heater controls.

I am hoping someone can help me. I have a 1999 Blazer that has been good to me so far. The other week I noticed when I have my control knob turned to heat for the floor it still blows out my defrosters and not the floor. Is there any simple fix for this problem or are we looking at an extremely expensive repair bill. My father has helped me in the past but is rather clueless on this. I phoned a car dealer and they are saying my repair bill would be $500+. We are thinking of trading it in for fear of other things going wrong. It has 84,000 miles currently on it. I would put up with cold feet but it is already getting old as it is still very cold out. Please help. Thanks.

I had the same problem in my 98 for about 5 months, and found time last weekend to take a look. (lots of cold feet) I'm not sure if it is the same problem your having, but this is what I found.

Take the under dash panels that are under the drivers side and under the center and move them so you can look from the drivers side floor. You will see two vacuum diaphragms, they look like squashed balls with a vacuum line in one side and a rod sticking out the other side. I found that the rod coming out the top was not connected to the flap that controls the floor vent. Some how it got disconnected? The rod on the diaphragm has a flat plate on the end with a hole in it, and the flap control (white) has a pin that goes into the hole. When the truck is started, and you switch from vent to floor and back again, you can see how things are supposed to work. I reconnected the two pieces, but needed a nut to hold the two together. I'm not sure what size cause the first one that I tried, worked. (lucky guess) The flap control is white plastic, and I was able to thread the nut on with my fingers. I didn't want to use a wrench, for fear of braking the plastic pin off. As long as the nut in snug and wont turn off, it shouldn't have to screw all the way on. My guess, is there was some kind of clip that held this together, but it fell off, because I didn't see any threads on the pin.

If you find that the diaphragms are connected the way they should be,(Rod/flap control & vacuum line) start the truck and move the climate control switch slowly to all the positions and see if one of the diaphagms are not working correctly. Could be a bad diaphragm, or it could be that the vacuum line is off the back of the climate control.

Or it could be something totally different.
I'm not a pro, but this could be the ticket to warmer feet.

Good luck!