Hi All,
I'm new to the forum and glad to be here. I have a 93 aerostar, 3.0 with 2 wheel drive. This last summer the heater core blew and had it replaced. The heater has always had a moderate not great heat output. It has overheated a couple of times severely before heater core replacement. Even after the heater core was replaced it still had moderate heat output. This fall replaced the thermostat but that did not help with output. The temp gauge has always read a little cold.

Our recent cold snap here in Wisconsin has brought things to a head. The temp gauge ran hot, the engine did overheat some (I suspect the antifreeze froze, thought I had enough) one midnight on the way home from work. Now there is no heat, the gauge quit working, the engine hoses get warm but not hot the way they should, and there is little heat in feed or return heater hoses.

Need help where to start troubleshooting and have limited funds so a mechanic is out of the question unless absolutely necessary...and baby its cold outside. All help and comments would be appreciated.

 

there is a vacuum tube that connects to the heater valve, is it connected to the valve?

check coolant level when cold, is radiator full up to the neck? Any white smoke when the engine starts?

 

Make sure the thermostat is installed correctly and is not blocking the hole that feeds the heater system. It happened to me. My heater output air was barely warm. I opened the thermostat housing and noticed the thermostat was blocking that hole. I replaced the thermostat with a new one making sure it didnt block it again and now i have really hot air. Also make sure you have enough coolant in your system. If not, you wont have any heat and the needle wont move much. Plus eventually it will overheat. I had to replace the coolant temp sensor (the one that controls the needle) too. I have a 3.0 engine and is in the front of the engine right below the thermostat housing with a single wire connector. Hope this helps.

 

Hope the best. Bought my 94 aero 10 years ago in MN. Brought it/drove it back to Cali. Still drive it. Regarding your interior heating problem, I broke a small diameter hose last year that resulted in a situation like yours. Once I repaired it, all was well. This vacuum hose to control the interior heating doors (vent, defrost,floor,etc) is located top left when you open the hood. My nylon(?) hose was creme color.