Hi there again...

I was driving back from the coast Saturday night and as I started to get further inland I turned on the heater in my R31 Skyline. Just on my feet, and my wife's of course.

About an hour later she suddenly revealed to me she'd been freezing all the way! While I had nice warm air blowing over my feet, hers were getting a stream of very cold air!

How could this be?

Duct might have come off or control cable possibly. My manual doesnt give a clear view of the heater assy.
Most heaters are a pita to get to unfortunately.
(The leaky heater core in my Subaru has been bypassed for 2.5years now because i'll need to rip the whole dash out and disconnect the a/c to get to it.)
Hope its an easier fix for you...

Thanks... but I don't think that's the problem...

Thing is, when stopped there is a good breeze coming from the ducts. On the driver's side it's hot, on the passenger's side it's cold!

I would have thought it all comes from the same source to the fan?

check your blend door and distribution flaps

_________________
http://www.healingchambers.com.au

What and where are they?

It still beats me that it can be blowing cold air when it's got the heater turned on. Isn't the supply the same for the whole system? Isn't there just one fan?

If you hvae heat on your feet but not passengers, then you can rule out the fact that it has nothing to do with the heater tap not working

The next step is what i said earlier

these parts are under the dash,
you will have a fan on one side which blows the air either over the heater core which then exits and then there is a door, now depending on what you select feet/face/window, the door will move and open a passageway through the ducting to desired area, now it's possible that the door can get jammed and not fully close/seal etc, you could have a duct that is loose, BUT you are getting cold air to that side though

Try it with A/C on too, and see if there is a temp difference between passenger and drivers footwell

_________________
http://www.healingchambers.com.au

I'll do all that tomorrow... but I still feel I am missing something...

Like I said, with the car stopped (ie. so there is no natural airflow through vents to disturb things) we have this split in the system. Where does the split come in?

The fan, you are saying, is blowing air through the heater core. So how is the fan also blowing cold air to the passenger's side? I hope you understand what I'm getting at here.

i do understand, and unless you know how these systems work, or have a basic understanding, its hard to explain it

how the temp is regulated is by how much blows through the heater core and how much bypasses it, and if the blend doors are faulty, or the distribution flaps are, then you will most likely get the symptoms you have

There very well might be a simple fix out there, but i have never dealt with an R31 before, other than the engine

_________________
http://www.healingchambers.com.au

Well, I'm pretty sure I have more than a basic understanding... that's the very reason that this has got me perplexed. I'll go have a look at it shortly, thanks for your interest.

Okay, found the problem...

The fan housing is above the passenger's feet and blows through the distribution box in behind the heater controls in the centre of the dash. There's supposed to be a foam rubber seal between the fan housing and the distribution box, so while some air is going through where it's supposed to, a lot is just blown out over the passenger's feet straight out of the fan housing!

Very difficult to remove, I have a spare in another car so I'll see if I can get it changed over, otherwise I'm going to have to improvise by taking it out as far as I can and gluing foam in there somehow. Not looking to be a real shapely job. I might try to put some kind of liner in the thing to help cover the gap too... like a plastic sleeve in the joint.

I'll post pics and let you know how I get on...

happy days

_________________
http://www.healingchambers.com.au

duct tape?

Was my first thought... but you can't really feed anything around behind the joint...

I'm actually thinking now that I might just jam rag up behind it, where the joint is closest to closing up, and tape the front, top and bottom, probably with some foam in place when I tape it.