Heater will not blow anything but luke warm air
 

My heat will not work on my 99 Civic hatch with a D16Y7

I have checked the following things:

Went under the dash to make sure the level is turning when I turn from cold to hot.
Heater control valve is opening and closing when turn the temp control knob
Bleed the coolant
Changed thermostat
Took off the heater control valve and made it wasn't broken and would open
Flushed the heater core with a water hose
Checked the fluid level

What is there that I can test?

Re: Heater will not blow anything but luke warm air
 

How hot is the engine getting? Do you have a water temp gauge? Whats the Outside temp? How long is the car running for?

Re: Heater will not blow anything but luke warm air
 

The engine is fully warm
I am only going my Si cluster temp
Outside temp has been from 39 to 56
Car was running for 20 mins while I was in the car messing with the controls under the dash.

Re: Heater will not blow anything but luke warm air
 

Bump on update

Re: Heater will not blow anything but luke warm air
 

Can someone please help?

Re: Heater will not blow anything but luke warm air
 

whelp, you pretty much diagnose and found nothing, replace your heater core, thats most likely whats failed

Re: Heater will not blow anything but luke warm air
 

You sure the outside air flap is closing? You can usually hear it change if you have the blower on full, then change from outside to recirc.

Re: Heater will not blow anything but luke warm air
 

Yes I took the glove box off and watched it open and close between recycle and fresh.

Re: Heater will not blow anything but luke warm air
 

might want to check your fuses also

Re: Heater will not blow anything but luke warm air
 

I'm not sure what else it could be, other than maybe a faulty thermostat or a slightly plugged/corroded heater core.

Re: Heater will not blow anything but luke warm air
 

Im gonna be diagnosing my heater problems pretty soon here and figured what all to check, but i've heard it mentioned on here more than once.. are there fuses for the heater?!

Re: Heater will not blow anything but luke warm air
 

like i said... replace the heater core....

Re: Heater will not blow anything but luke warm air
 

the only fuses for the heater are for the blower motor, if you got the speeds then the fuse is good. I have a pressure tester for heater cores that i bought off the tool truck that comes by my shop. It was around 160 bucks. My advice for u is to pull the dash and change the heater core. Being a 99 its probably never been done yet. sounds like it is partially plugged. Should blow out 80+ degrees out of the center duct, mines blows around 100 degrees and is less than a year old. just break down and change the heater core.

Re: Heater will not blow anything but luke warm air
 

have the same freaking problem man...i can hear the blower working but not much air comes out...i dont know what could be wrong...i've checked everything...i can feel a little bit of warm air come out but its crazy cause i put it on max.....

Re: Heater will not blow anything but luke warm air
 

Bump on old thread....

I got the same problem. But my car is 21 years old, what kind of heater core should I replace it with? Anything from my era is sure to have or encounter the same problem.

Re: Heater will not blow anything but luke warm air
 

Bump on old thread....

I got the same problem. But my car is 21 years old, what kind of heater core should I replace it with? Anything from my era is sure to have or encounter the same problem.

Re: Heater will not blow anything but luke warm air
 

you just order a new one bro, don't take a heater core from an old civic

Re: Heater will not blow anything but luke warm air
 

Suddenly both my heater and my AC don't work on my 96 Honda Civic Ferio -- I mean, it blows air, but it's cool-ish air (not "cold" as in AC-cold) for both the heater and the AC.

I checked all of the fuses, and nothing there, but there are these LARGE encased fuses under the hood on the passenger side of the car (right hand UK drive) near the windshield, and one of them seems to be dead (my friend tested it with some gadget). Could this be the source of the problem?

It's a Japanese import, which has never given me any problems, except a chronic headlight problem. Any suggestions would be greatly appreciated!