i have a 1992 mazda pickup b2600i. the heater blows cold air i changed the thermosat,and the heater core does?

Question

and i changed the thermosat,the heater core does not leak antifreeze what could i do because winter is right around the corner thanks bill

Answer 1

Maybe the connector hose has a hole in it or has come loose.
You may be able to get by with a small ceramic heater with a plug that fits the cigarette lighter. Heater core replacements are $$$.

Answer 2

The thermostat won't cause the heater to blow cold air. Hopefully you have a engine temp guage to tell you if the engine water temperature is ok. If not, just feel the radiator hose when the truck is warmed up.
Heaters usually blow cold air because the vent controls aren't working right. You need to reach the heater coil to see if it's hot. Some of them have valves that allow the coolant to flow through the core.
The core can also be plugged. Somebody can check that by taking the water line off that goes to the core and trying to run some water through it with a garden hose. If it's plugged, don't try to fix it. It will be rotten from lack of circulation, and if it's the original it's at the end of it's lifespan anyhow.

Answer 3

After you changed the thermostat did you bleed the cooling system? If not, this could be the cause of a no heat condition in the cab. After opening the cooling system to replace the thermostat, air may have gotten in and now that its sealed up an air pocket has formed cutting off or hindering coolant flow. Try bleeding the system, if that does not work check for a blockage somewhere, possibly in the heater core itself.

Answer 4

heater control valve cable or vacumn line