My 1996 XJ seems to have an issue with the heat, or maybe it just doesn't work the way I expect it to. In AC mode, air comes out of all the vents. Same with "vent" mode. Defrost works normally. But in "heat" mode, air only comes out of the floor vents. It not a huge issue because heat rises anyway, but I was just wondering if that's normal.

Also, I noticed that the blower is pretty much "off" or "full blast." Anything less than the full blast position and it barely moves any air.

 

The function is normal. It goes up, down or vents. There is no middle. I wish there was a blend.

Is there air blockage in the heater box? Mine was full of insulation. Is better now. You only have full and nothing other than that? If that's the case, the resistor is borked.

 

The heat NEVER comes out of the top vents. The only time I get air out of the top vents is if I have the AC on, or have it in the "vent" position.

 

Sounds like it might have vacuum problem then. In the future, try having the issues you're having down and not piece it together.

 

So when it's on vent no warm air comes out?

 

I tried to explain the issue thoroughly in my original post, I'm sorry if I didn't explain it well.

In "vent" mode some warm comes out, but it doesn't seem as hot. If I'm not mistaken, "vent" just means that it takes air from outside the vehicle instead of circulating the inside air, right?

 

I'm not sure here, but anyone with vent issues should know they are dependent on the vacuum reservoir down behind the bumper. See the diagram. The large line "charges" it, then the small line coming back operates stuff. The "ball" might be hanging by one line, cracked, or missing altogether. That and it's lines are something to check.