Hi all.

Many thanks in advance.

The heater is not working. Fan blows great....just cold air. Anything you can think of to check?

 

Is the engine warming up? Or does the heater never get hot? If it never gets hot then there are a few things you can check. One would be a blocked (inside or out) heater core. Another would be a plugged up heater hose not allowing coolant to the heater core. And finally the door to the heater core may be stuck shut so the air is bypassing the heater core. I'm sure there are other possible causes, but those are what I've got in mind right now. I'd honestly check into option 3 first. A linkage or something may have just gotten jammed keeping the blend door to the heater core closed so no air is passing through.

 

I would agree with the thread above, I would check the air mix doors, b/c my 90 did the same thing and i found piece of plastic. It was the control arm on the air mix doors. i took apart the dash and used jb-weld to put it back on. hope this helps