i have an 05 monte ls 3400. when i turn my heat on in the morning i crank the heat to warm the car up and i get no heat. air still blows but its just cold air (temp of air outside) i was thinkin heater core.....anyone have any ideas of a DEFINITE fix?

 

Well how long is your drive??? You need to wait till the temp needle hits 100 for warm air to come out.

 

unless you are loosing antifreez and have a wet floorboards i dout it's a bad heater core more than likly a bad thermastat

 

Has the car been overheating at all? Can you smell coolant? When it gets up to temp does it just keep going or does the thermostat seem to open?

If its over heating and cold air is coming out I would take it to get a compression test done to check on the head gasket. Before I did that I would check the thermostat first.

 

most likely potential problems:

thermostat
no coolant/leak

if it all of a sudden just happened, its most likely one of those judging by how old the car is, id say check those first before making an assumption

 

Sounds like either the heater core has gone bad, or the thermostat is bad.

 

If the heater core was bad, i'd think you would be leaking coolant inside the car. Sounds to my like maybe your low on coolant, and have a leak elsewhere. The 3.4L is known for gasket issues. Check you coolant level, and make sure its full. If its not, get a compression test, and see where the leak is, then get it fixed.

 

low coolent or the thermostat is stuck open

 

Air in the coolant system would also cause a no heat condition. If you are not leaking\ low on coolant, and thermostat is good, that is what I would suspect. I had a car that we did everything, and could not figure out why the heater would not work. Turned out to be air in the heater core. We had to jack the front of the car up, and bleed the system for the 4th or 5th time to persuade the air bubble to come out of the heater core.

 

the air bubble it was.....thank u all very much for ur help