Inside my 1991 Miata, the water literally pours onto the rug on the
passenger side when the A/C is on. I turn off the A/C and no water problem.
Should I assume that the hose has become loose inside and to get it from the
Also, should I dismantle the glove compartment. I see two screws at the base
of the glove compartment. Is it as easy as just unscrewing those two screws
and once the glove compartment is removed, that I would have easy access to
the hose that is either disconnected or in need of unclogging?
Possibly, but the overflow box is probably clogged where the hose
connects. There will be a short rubber hose running from the plastic box
out through the firewall.
Disconnect this hose at the box, it is only held on by pressure, then
push a screwdriver, coat hanger, or whatever works into the opening to
dislodge the debris.
Get ready for some nasty water to come out and put the hose back on as
quickly as possible. Laying a towel down first is a good idea.
If a lot of water comes out, then that was definitely the problem. The
entire process takes only a few minutes.
No need for any of that. Just pull the carpet back a bit and you will
Opening things up from the inside will allow the collected water to gush out
on the carpet. It also will break any seal between the firewall and the A/C
box. Clearing the drain hose is a much better idea, and normally solves the
True, it is a better way to do it, but that requires getting underneath
the car and using something flexible to run through the curve in the
I like staying out from underneath the car more and more as I get older,
and I've never had a problem with a seal leaking after the drain tube
was removed and replaced.
Ok, I found the black rubber drain hose/tube. Unplugged it from the plastic
box and there was no water pouring out. I poked up into the plastic box with
a vinyl probing tube (I did not want to use metal) and no water or debris
could be seen. It looks like the plastic box is debris free!
Next, I pushed a flexible vinyl tube, which has an outside diameter smaller
than the inside diameter of the rubber drain hose, down the length of the
rubber drain hose. I pushed it into the drain hose until I could see the
vinyl tube dangling under the car. I had to straighten out the rubber drain
hose to reduce tension on the vinyl tube while reaming the drain tube, and
that made it easier to push it through. I think it cleaned it, if there was
a problem with dirt in the drain hose.
If I had this water overflow a few days ago, for the first time ever, but I
could not get water or sludge pouring out when I disconnected the drain tube
from the plastic box, WHERE DID THAT WATER COME FROM?
Is it possible that water poured out from above the plastic box? Also, how
come there are no illustrations, photos, or anything to clue us in on what
the interconnection is with all these A/C parts under the glove box? Its
like working in the dark, you have no idea of what to do next.
That was my thought, and if so, then it probably will not clog again for
I would run the A/C and see if it happens again. If it does, try
unclogging it as soon as it starts leaking water and see if there is any
more water in there.
That is the only place for water to leak from regarding the A/C, though
it is possible that the box itself is cracked or otherwise leaking.
I agree, not much room to move around down there. I dread any work
behind the dash. Being skinny helps a bit, but not much. :-)
Speaking of skinny, I won't say I'm not skinny but I can't even put the
cover back on the fuse box, had to get help.
Heck, it takes me 3 minutes to put the car on to go somewhere and
equally long to take it off when I arrive!
XS11E, Killing all posts from Google Groups
The Usenet Improvement Project: http://blinkynet.net/comp/uip5.html
How long had it been since you last used the A/C when you did this?
That would definitely clear it.
Same thoughts as XS11E, it may have drained slowly.
Are you driving in a humid area? The A/C can produce a lot of
condensation around here, and a partially clogged drain would allow the
box to overfill, even if it emptied the water from the box over time.
The miata enthusiast manual and the factory service manuals show this,
but nothing is very easy to get to, and there is wiring EVERYWHERE, lots
of sharp screws to cut yourself on too.
Oh the joy! :-)
Years ago, the A/C stopped working because of a leak in the system. In late
Spring, of this year, I had the A/C fixed and it worked since then. I had
been using the A/C every day until the flood happened. Then I stopped using
the A/C for 4 days. After which I reamed the drain tube and checked the
plastic box. Now it seems to be working ok but I do not see any water leaks
inside the car, yet.
When people report of leak and the plastic bok is sealed, how does the water
get out? For example, the hose is securely attatched to the spout on the
plastic box. I had to really pull on the rubber hose to detatch it. Go
Its a little humid now but bad.
I wish someone could show photos of this someday. Surely, there are Miatas
of the M1 class that have A/C and where the owners have the dash off and
good views of the plastic box.
Apparently it's only sealed at the bottom and once enough water collects it
can leak over "the top". When I would make a fast left turn, water would
pour out on the right side of the passenger footwell.
Thanks, this is what I pictured happening. Water has to escape either
through the intended primary route (DRAIN HOSE) or through some other means,
overflow. I think I will do some more probing up into the plastic box but
with a wire brush that is less likely to poke though something critical.
I have removed 2 of them and never bothered to look to see how they are
put together. I probably have one sitting around, I will take a look at
it and see.
It makes sense to have a safety overflow on the box because it can't be
good to have water back all the way up to the A/C system.
The box is made of fairly thick plastic. You would have to caveman it
pretty good to puncture it, but being careful is never a bad idea.
Ok, you have me curious enough.
I will dig up that part, plug the drain hose outlet, fill it with a hose
and see what happens. It may be next week before I can get to it.
You can tell I have a really exciting life, eh? ;-)
Taking a quick look, the water collects in the bottom portion of the
plastic box once the drain is clogged, then follows the path of least
resistance, which is the section where the vent tube is attached.
The vent tube is attached considerably lower on the passenger side,
(U.S. models), than on the driver side, which makes sense.
Better to have water on the floor than under the dash.
The box is sealed, it might leak if it was full of water, but it would
not pour water out of the top in any large quantity even if the other
openings were blocked off.
My box is still in place even though most of the A/C was removed, and
there was a noticeable gap between the box and the vent tube where water
would obviously pour out if it was collecting there.
The car is 16 years old, and it was probably never watertight at that
connection, but hooking it up more securely would cause the A/C system
to work better overall on a similar car with working A/C.
That was poorly explained. Obviously the box is not sealed, it has
openings for the air vents. I meant that it has no overflow opening
other than the lower vent hole.
The upper and lower sections of the box are sealed, which again only
makes sense because the A/C system would leak a large amount of air
underneath the dash if the two sections were not sealed.
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