The smell in passenger compartment is like cat urine. It causes me
bitter taste and tingling feeling on my tongue and headache.
I opened all doors to let fresh air in and then closed the doors.
Then, 10 minutes later, the smell came back (the engine was off all the
time). To eliminate the heater core as a source of the smell, I
bypassed the heater core and flushed the heater core with tap water.
The smell persists.
Can it be the leaking refrigerant R134?
All the tips you've been given should have covered any smell you're getting.
Refrigerant shouldn't have a smell to it and if you were leaking you should
see a difference in the AC and/or defrost.
I think one of the tips you got before from someone about something getting
in the car from a previous owner is the answer to your problem. I suggest
you take it to a detailer and let them do a thorough cleaning.
I did dome research and found that R134a (the refrigerant) does have an
ether-like odor (i.e., like urine smell). So, ,my cooling system is OK
(the smell persisting even with cooling system using only pure water
indicates the the smell does not come from cooling system).
I now switch my attention to AC system. I will use 2 steps: First, run
the AC for awhile and hope that the spome leaking seals (if any) will
work again. If the first step fails, the second step will be AC system
According to the r134a MSDS
you are correct, there is a "faint" ether-like smell. If you associate that
with a cat urine smell then I agree. However, the MSDS states it takes a
high concentration to be irritating to eyes, respritory system and etc. It
also states under these conditions the adverse effects may be long-term
harmful. If you truly believe this is the problem then you need a
professional diagnosis rather than a process of elimination or by trial and
As I said before, I suspect if you were leaking enough refrigerant to
warrant a high concentration in the cabin then you would have noticed the
difference in the cooling and/or defrost system(s). But, to err on the side
of caution, you need to get your AC system checked by a professional before
you proceed any farther.
If they find no problems, you can also talk with them about the different
odors an AC/heating system can produce and the products available to quench
them. This may help solve your problem.
Hi davidj92 and all:
After two months of intensive labor and thinking and elimination of one
possible smell source after another, last weekend, I finally found the
source the cat-urine smell in my Camry 2002 passenger compartment
(cabin)! Guess what? It is the leaking AC chemical (i.e., refrigerant
R-134a + oil). Unbelievable huh!
I can't believe it myself. Before the discovery, a mechanic even
gave me a chance to smell some R-134a to prove to me that the cat-urine
smell in my cabin does not come from leaking refrigerant R-134a. It
turns out that refrigerant R-134a does not smell like cat urine at all.
But I insisted that the refrigerant in my AC system be removed
(because that's the only smell source left). To my relief, after the
refrigerant removal, the cat urine smell in cabin stopped.
So, I theorize that R-134a is kind of chemically active. When escaping
from the portion of AC system behind the firewall (e.g., from the
evaporator core), the refrigerant may chemically react with some stuff
in the evaporator case and create all kinds of smells (cat urine in my
case). You may have heard a lot about mold and other stuff in
evaporator case. I think those stuffs are ready to react with leaking
R-134a to create all kinds of odors you never expect.
Thank you all for your supports and suggestions. I will let you know
if my solutions for the leaks work.
There was a Seinfeld episode where a car got a smell they could not get
A used car, so you have no idea what happened inside. Ive heard of dead
people, squirrels, and mice and the smell never goes away. Maybe its in
the doors! take it all apart! you will find it someday. Or get the thing
I'm glad you posted this.
As far as I know, the refrigerant has little odor. BUT the oil that is
present in the
refrigerant certainly could.
To me, polyalkyleneglycol fluids do not smell like cat urine, but they can
a sharp odor.
Polyalkyleneglycols may be used as refrigerant lubricants, and they are also
as brake fluids. (Not the same ones, but same generic chemistry.)
Recently, I noticed the smell in my Dodge van, and immediately suspected the
brake booster or master cylinder was leaking. I performed the traditional
for the brake booster, and checked the master cylinder, but everything was
The brake fluid did not have a strong PAG smell anyway.
Now, I have noticed my airconditioner is no longer working. Refrigerant has
out. And what I was smelling HAD to have been the refrigerant lubricant.
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