whats wrong with my heater

[9150ho]

with my gauge telling me the car is warmed up (around the o of normal) the heater still blows cool/warm air. if i switch the knob to blue for cold there is a very noticeable difference from the red for hot. but it isnt what it is supposed to be. what could it be? any ideas?
sean

 

[IndyBlk5.0]

What degree of thermostat do you have?

Is your passenger side kick panel carpet wet?

Your heater core could be getting clogged...

 

[fordman54935]

It could be a couple things.....You might have an air bubble trapped in the heater core or hoses, or your heater core might be on the way out. Does your windshield fog over or do you notice wet carpet on the passenger side?

 

[9150ho]

my carpet was a little wet and i thought it was the heater core but the wetness has no color when i soak it up with a paper towel nor does it smell. and i cant find a wet spot on the underside of the dash where a leak from the heater core would be seen. i dont think it is related. i think the air bubble sounds like a maybe. i will try that. thanks.

 

[RsStanG1987]

Try checking your coolant. Flush your cooling system the heater core could be cloged.

 

[Black1987Stang]

Is your coolant level going down?If so then the heater core is probably on its way out.With the engine at normal operating temp, and the heater off, check the two heater hoses. If the one is hot and the other isn't,(clogged) then the heater core is most likely your problem, i may be wrong but thats what i say. Sounds stupid but pop off your heater knob and check the back of it, make sure its solid, mine was broken and it still turned back and forth but only turned the metal knob a little bit, and that caused the heat only to change a little bit.

 

[bryanrevans]

Does you damper door open and close??The hot and cold red,blue is determined by the DAMPER door up inside dash.When the red side of controlls is operated the passage leading to heater core chanber is exposed..When blue is operated the heater core is shut off and damper door is pushed over to open vent side!!!!!

 

[9150ho]

i discovered something, this morning i went out and started the car, and popped the cap on the radiator to burp the system. I was sittin there stareing at it when my a/c compressor kicked on!! than it shut off, and kicks on and shuts off over and over. what the hell is that about? i had the knob on heat and the other knob on high and the other knob on defrost. any ideas?

 

[RsStanG1987]

maybe your heater controls are f'ed up

 

[smac61]

The compressor always runs when the control is set to defrost, no matter if you have it set to hot or cold. The cycling of the compressor means that you are a little low on freon (the compressor has a cut-off built in to protect it from damage if the freon leaks out)

 

[9150ho]

dangit, i thought i was on to something

 

[Euphoric306]

one time my heater wasnt putting out hot air... turns out my coolant was low, discovered a crack in my radiator...

of course, if ur coolant is as low as mine was, ud be having more problems than just cold heater air

 

[sgarlic]

If your car reaches normal operating temp. and stays there (doesn't overheat, doesn't take a long time to warm up), then it's not your thermostat.

If you remove the temperature select knob, and use a duckbills or vice gribs to turn the peg all the way to the hot, and it still blows cold, you can eliminate the knob as the problem.

Open the passenger door, and look up under the dash while somebody turns your heater on. You should see the door physically open and close as your friend cycles the heater on and off.

My last try would be to just change your heater core/heater hoses. If you've never done it or you suspect it's leaking/malfunctioning, just do it now and get it out of the way. There's plenty of info. available on how to do it, and if you have a weekend and a buddy to help you, you'll probably be glad you did.

Even if this turns out to not be the problem, you can flush your system while it's drained, and you will burp out the bubbles when you're done, eliminating that as a possibility.