I am having problems with my car fogging up this winter. I have had to scrape the inside of my windows many times. I believe this is either due to a bad heater core or a problem with my recirculation vent not opening.

The car does heat up (Slower than I would prefer). I do not smell anifreeze in the car and it takes a little while for the car to fog up so I think it is the recirculation vent not opening and recirculating the inside moist air.

Is there a fuse that could cause the vent to not open?

Where is this vent located, is there a way to see if it is opening?

What could fail to cause it to not open?

If there is a little crack or hole in the heater core would I smell antifreeze? Would the car still heat up? Is there an easy way to know if this may be the problem? I hope it is not, I have heard I may have to pull apart a lot of the dash to replace it.

Any feedback would be apprediated.

 

Usually the fogging up of the windshield is the first sign of a bad heater core. Should leave a film on the window that is extremely hard to take off. You might not always smell the anti freeze. But feel your carpet under where your feet or your passengers feet would go, sometimes it may be wet. Heater core usually sits in a plenium box that is sealed. Never replaced mine on this car, i will have to check my repair manual tomorrow. Ive done my ford f-150 and had to remove the entire dash.

 

You have to remove the dash in the Alero to get to the heater core also.

 

I will check tonight, but I don't recall a film on the windows or a wet floor. Is it possible the car is stuck in recirculation rather than opening the vent? If so, is there a fuse that controls this that may have went bad or would it be the BCM that controls this?

 

When mine changes fron recirc to outside, you can hear the vent moving, especially if it's cold. Put your heater fan on low, and change between recirc and outside, listen for movement near the glovebox.

 

I checked and could hear something everytime I switched between recirc and outside. However, the symptoms for a bad heater core were not there. I decided to start digging for the recirc/vent door. I took out the glove box because that seemed very easy. To my surprise the door was right behind the glove box. It turns out that the vacuum actuator was working, but the flange on the plastic door that mounts to the actuator had broken so the actuator was not connected to the flange and the door was not opening and closing as I suspected. I am not sure what the door is called (Blend door, actuator door, heater control door), but I checked with every parts store I could find and no one had this door. I went to a dealer and they said they think it is the heat control door so they were going to order that. It will take a week to get in. I will know if it is right on Friday. If it is not, I am going to a salvage yard to pull one from a scrapped car. By the way, this part is nearly impossible to get out, you have to take apart the whole dash to get to one fastening screw that can not be reached any othe way. I even tried drilling a hole through the outside body of the car to get to the screw, but there are components above it that prevent removal. I could only see it through a 1/8" gap and with the use of a flex mirror and flashlight. I really dislike working on the HVAC system in vehicles, because they are always simple fixes that are impossible to get to.

 

I just replaced the heater core on my '02 Alero. OMFG. Ridiculous. I'm pretty mechanical, and it took me 7 hours and a lot of cussing. They sure don't make it easy to get that thing out, and it's even harder to get it back in.

When the mechanic wants to charge you a fortune to replace yours, now you know why!

Beer in my immediate future!!!!!