targa2

I have a '95 Hatch Si and warm air comes out of the vents after the engine has warmed up even when the outside air temperature is cool. The air coming out the vents is definitely warmer than the outside air. I have the temperature slider all the way to the cool. This only happens after the car has been driven for awhile, not at start up. Is there a vacuum line or something that would be allowing a valve to let hot water flow through the heater core? Anyone experience this before?

AnToNy

when i had my VW it did the exact same thing! it was the heater core. ended having to put a manual bypass valve under the hood. hope this helps.

targa2

Anyone know how the Civic heater system works that can offer a suggestion?

allmotorEG-SI

if you get a manual on the car, it will probably explain how the heater system works. What ever it is that makes the hot air come in to the car is probably jammed open & can't shut.

Does it get any hotter when you slide it to the far right? If it doesn't then my guess is it is just stuck open.

jerbear!

i would also like to know

johnnycivic66

You should try pressing the recirculating air button (the one with the "u-shaped" arrow circulating arrow around the car.) If you don't have that button on, then fresh air will come through the hood cowl, and will indeed blow hot air on you after the engine has heated up.

allmotorEG-SI

the only time i ever get hot air on my car(94si) is if its not as far to the left as possible. dispite what button is pressed, you should be able to turn off the hot air.

ICEDOWT

on my 96 it does that too so i just hit the recirculating button and it stops doesnt let any air pass through

targa2

allmotorEG-SI -
The air is much warmer when the temp slider is pushed to the right. That seems to work normally.

johnnycivic66 -
The warm air comes in when it is not recirculating so I guess you are saying that the air is coming through the hood cowl and being heated up by the engine. I like the fresh air, so that is how I have it set most of the time. I guess I will live with it. I also have a '94 Del Sol DOHC and I don't experience any warm air coming in from that car in the same configuration, so I thought that possibly something wasn't closing properly.

thanks

allmotorEG-SI

I really don't think its working properly. I have a '94 Si and I can stop the hot air coming in. If you have the fresh air button pressed in and the temp control lever is all the way to the left, you shouldn't have any hot air coming in. On the temp lever it shows an overlap of blue and red. when sliding it to the left and passing all of the red label, the last inch or so should be just blue, you should feel some type of extra resistence or somthing like the heater vent is shutting. If you don't feel anything like that and its always just a 100% smooth sliding action, then your temp adjustment lever may not be functioning correctly. Possibly misaligned. But you can stop all the hot air.

AnToNy

maybe the inside of the lever broke off, who knows

BigMig

dude my civic was the same way but it was just that the system needed to be on recirculate instead of fresh air. the fresh air setting brought in the warm air from the engine bay.


Modified by BigMig at 1:23 PM 6/29/2004

SolObsession

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by BigMig &raquo;</TD></TR><TR><TD CLASS="quote">dude my civic was the same way but it was just that the system needed to be on recirculate instead of fresh air. the fresh air setting brought in the warm air from the engine bay.


Modified by BigMig at 1:23 PM 6/29/2004</TD></TR></TABLE>

Same thing in my sol.

ykracing

okay, let me see if I can help you out a little on this one.

If you look at your engine bay, coming out of the firewall behind the intake manifold, but more on the passenger side, you will find two heater hoses. One of them goes into a little box (valve) about 3 inches off of the firewall, probably mounted via a metal bracket.
That is the valve that controls how much coolant is sent into the heater core to warm up the interior of the car.

That part is likely the problem. Now, there are two possible fixes.
1) replace the valve.
2) try adjusting the steel cable/rod to tray to make it close further.

Testing:
I personally would disconnect the cable from the valve (see "adjustment" section below)
and close it as far as you can, and drive around to see if that fixed it. If not, you probably need to replace the valve. If it did fix it, move on the the adjustment section below...

Adjustment:
there is a jacketed cable that has an eyelet on the end that hooks onto the lever of the valve. and there is a small "fold-over" steel clip that holds the jacketing.
You can try to un fold the clip to release the jacketing, move the valve closed further, and the re lock the jacketing into the clip.

This may work, it may not, and when you find all of these parts it will make more sense...
try it out, and see.

darkcvc

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ICEDOWT &raquo;</TD></TR><TR><TD CLASS="quote">on my 96 it does that too so i just hit the recirculating button and it stops doesnt let any air pass through</TD></TR></TABLE>