Heater core changed three years ago,I changed Thermostat Heater still blows cool air.
VENT TO HEATER CORE IS NOT CLOSING................
You have vacuum line leaks somewhere.
The heater valve may not be engaging or the heater core may be blocked.
most likely your heater controls run via vacuum lines. cracked or broken lines could cause this.
If it still blows cold when it is at running temp, check the engine thermostat, its probably stuck in the open position.
Your heater coil is bad.
The heater core is plugged. Blow it out with a compressor. If that does not work replace the heater core.
Try flushing the heater core.
The thermostat is not the issue. The thermostat regulates the engine temperature, but not the heater core temperature. There is a valve going to the heater core that is not closing all the way. It may be broken, clogged, or not actuating.
Interior heat uses the engine heat. If the engine is still cold, the heater will blow cold. If the engine is warm and the heater is blowing cold, you have a problem with the heater. Check the water in the radiator and see if it is rusty. If it is rusty, change your coolant, thermostat, and hoses. Look at the heater hoses when someone steps down on the gas pedal. If a hose collapses, replace your heater hoses. Otherwise take it to a mechanic.
I have a 99 bravada, and have had no heat for over a year... until today. I was told by the dealership that I needed a new thermostat, so I had one put in last winter... that did nothing. Today, I had the heater core flushed, and Viola! I have so much heat I had to open my window, and I live in western NY! good luck! Just blow compressed air through the heater core
I would expect a plugged heater core.Take your hand and feel the two heater hoses that pass thru the firewall on the passenger side; if one is hot and the other is much cooler, than you heater core is plugged and needs replacement.
Check your manual. There is a fuse for the seat motors, pretty sure it is independent of anything else.
Sounds like you have an internal heater box issue. Possibly one on the mode door motors quit or you have a broken door inside heater box. To access heater box, you have to remove entire dashboard assembly. This is not too simple of a task.
you might want to check and see if the heater core is bypassed
sounds like your heater core is plugged up with gunk install a new one
thermostat probably damaged or stuck....and worse case scenario....your heater core is going out.
If the ballast on a fluorescent light blows the lamp will not work.
The AC and heater are completely different subsystems. The heater relies on heat generated by the engine and circulated by the engine coolant (radiator fluid) while the AC uses a belt driven compressor and separate fluids. Their only normal commonalities are the blower motor (which you said works), the ducting and the control head.
It doesn't have a crank sensor. It still has a fully functional distributor.
You have not bleed the air out of the system after you installed the t-stat, causing the heater not to work and the engine to overheat. Use a coolant filler that screws into the radiator and get the air out
Heater Airbound? Heater control cable not working? Heater core plugged?
To confirm your problem, the fan blows air but it is not heated?? I am not sure if there is a heater core in this car. The heat is generated in the engine and is transfered by a series of water pipes to a heating element(radiator) under the dash-board, the fan blows air over this radiator, it heats up and blows into the car. Things to check 1. see if the mechanical links between the temp. switches and the valves which control the flow of hot water into the radiator are functional.