My issue is that no heat comes out of the air vents, even when I've set the climate control to 90F.

There are no other symptoms, and the temp gauge shows the normal setting when the engine is warmed up (slightly below halfway). Cold air works just fine. When turning on the front defroster, the a/c kicks in and it gets quite cold.

Anyone have a guess as to what the problem is? Though not a critical issue, it sucks to be freezing when I'm driving.

I am trying to get an appointment today or tomorrow with a service shop, but it would be nice to have some preliminary idea as to what's wrong.

Thanks for any help.

 

I believe the way it works is as follows. When you turn on the heat in your car the water/antifreeze that is used to cool your engine is diverted through a coil system before being returned to the radiator to be cooled. These coils are inline with the pipes that carry the air from your intake to your vents inside your car.

From what you are saying, the air is blowing and will get cold, but will not get hot, I would assume that something is messed up with that coil system. either the valve that is suppose to open is not or the coil is plugged with rust or debree maybe. P{erhaps the thermostat is never sending the signal for the valve to open. I dont know but would assume it was something like that. Others may know more.

 

I'm hoping it's something simple like the valve not opening. Adjusting the temp to cold works fine. The colder I set it, the more cold air blows out. It just doesn't work for heat.

 

thermostat maybe???

 

well it cant be the thermostat for the engine or the car would most likely be overheating (and you would get hot air)

My guess would be in the hvac control or the part that controls the amount of coolant to the heater

 

I have the same problem but backwards, the heater is fine but the a/c doenst work.....

 

Well, you didn't tell us what year your car is!

Secondly, whoever said that a stuck valve would be cheap, guess again! It's $250cdn with taxes and labour from dealer.

 

i have the same problem on my 04 accord 6mt. no heat. i tried to bleed but no luck

 

It's a 99 TL.

 

read my reply to "iggy" thread. it may solve your problem

 

Well, I stopped by a shop yesterday, and it turns out the culprit is this "lever" that everyone is talking about. Mine is working intermittently. When I move the temp to either extreme (60F & 90F), the tech can see the lever moving, but it sometimes gets stuck.

So I'm going to get myself a replacement. The part itself costs ~$220, so it's not cheap. But it's too annoying for me to have to get out and manually "help" the level move itself.

Thanks to everyone for helping to diagnose!

 

Maybe try lubricating the existing lever before you buy a new one. sometimes a little spritz of wd40 will save the day... and in this case $220. Even if the hang is on the inside then when you take it off shoot a little wd40 inside and manually move it a few times and see if that loosens it up.

If the part was less I would say just replace it but at $200+ i would see if i could fix it.

Just an idea.

 

I've got a 1999 TL where the heater suddenly has stopped working. I saw some other folks with a similar problem. i've checked the fuses and they're good. On one of the posts, I saw there is a lever for the valve that may be hung up. All I'm getting is cold air. Can someone explain where I can find that lever so i can try a shot of WD40 before I take it to the dealer? Thanks.

 

My heat is back and all is working fine. It turned out the culprit was the air mix motor, which resides behind the dash. I also used to have a "fluttering" sound come from behind the glovebox, but I had always assumed it was debris that made its way to the micron filters. That fluttering sound is now gone. So perhaps the sound was actually the motor slowly dying.