Help identify my mystery aroma!

May 23, 2007 3:26 PM

What is the smell in my car?

Over Thanksgiving (USA - so late November), my sister and I were sharing my car, a '95 Corolla wagon. One day she came home and said that the car smelled pretty rank inside and she didn't know what it was. Sure enough, it did - if I had to describe it, the closest I could come up with was rotting squash. We tore apart the car looking for the culprit, and found nothing. After about a month, I didn't smell it any more.

Starting a few weeks ago on a hot weekend, I started smelling it again. It's just as oppressive as it was back in November. This is a good five months after the initial smell. Now, I lead a filthy enough lifestyle to know that even a dead rat stops smelling after a while. What the heck could this be? I've gotten the car washed and vacuumed, and also had a yearly maintenance. No change. The smell is much stronger in the front seats.

My boyfriend suspects that one of my sister's friends hurled in the car and she failed to tell me. This is possible, but in my experience vomit smells nauseate me. This one doesn't (thank god)...it just smells funny.

Is there anything I'm not thinking to check?

posted by crinklebat to travel & transportation (20 comments total)

get the a/c checked. my cousin's car ran out of freon and it smelled horrific.

also, you probably haven't used the a/c between november and now.
posted by thinkingwoman at 3:30 PM on May 23, 2007

No, it's not the a/c. I used it the weekend before last and the car smelled better with it on - like the dentist's office.
posted by crinklebat at 3:32 PM on May 23, 2007

Would you characterize it as "sweet and pungent"?

From here:

Question: 2002 Dodge Neon, miles: 76,320 Seems to run fine. However, on several occasions I have noticed a distinct sweet smell odor in passenger cabin. In a parking garage this week, I noted the smell while standing outside the car in front of the engine compartment. There aren't any leaks on my garage floor and car idles and runs smoothly.

Answer: It sounds like your radiator is leaking a little. The coolant gets on the radiator cooling fins and evaporates to give you a sweet pungent smell. Replace the radiator and your problem should go away.
posted by CKmtl at 3:37 PM on May 23, 2007

Or something in/under the carpet. Spilled milk?
posted by rhizome at 3:38 PM on May 23, 2007

I bet it is mold in the AC and vent ducts. This is a common question/answer on NPR's Car Talk that gets lots of laughs from Tom and Ray.

The solution is usually something along the lines of spray them with lysol, see if that kills it, then take it to a professional.
posted by M.C. Lo-Carb! at 3:40 PM on May 23, 2007

CKmtl, good guess. I wouldn't call it sweet - and actually the radiator is the newest part in the car (replaced last year) so I'd be really annoyed if it was cracked again.
posted by crinklebat at 3:42 PM on May 23, 2007

this is in no way a definite answer, but consider the following:

a rat did get into the car last thanksgiving, got smelly, then stopped. fast forward to a few weeks ago, and then a different rat found the same spot in your car.

or maybe antifreeze, that stuff stinks.
posted by ArgentCorvid at 3:46 PM on May 23, 2007

Sometimes people who don't like you will store shrimp in the hubcaps.
posted by b33j at 3:46 PM on May 23, 2007 [1 favorite]

My sister's car once started smelling for no apparent reason. It turned out that water was somehow getting into the spare tire well. I can't recall what a rotting squash smells like, but I'd say this smell could well have been mistaken for a dead animal. Looks like you'll have plenty of places to check. Good luck finding it.
posted by gauchodaspampas at 3:55 PM on May 23, 2007

What kind of weather have you had? And are you sure that there are no leaks in your car?
posted by dilettante at 4:00 PM on May 23, 2007

Catalytic converter.
posted by JayRwv at 4:09 PM on May 23, 2007

dilettante, as I said, the smell came back during a hot weekend. We've since had cool weather and it hasn't dissipated. As I remember it, this was a warm Thanksgiving - however, it was a warm winter in general and the smell definitely went away until late April.

I'm not sure, as far as leaks - it rarely rains here and I park in a garage so it wouldn't be noticeable to me.
posted by crinklebat at 4:33 PM on May 23, 2007

In my experience, antifreeze smells a lot like pancake syrup. And don't discount the possibility of an animal getting into the car. Have you found anything that looks like torn up tissue paper? Something that could look like nesting?

A mouse made it's way into my wife's cars ventilation system. We couldn't figure out why the fan wasn't blowing any air till I took apart the dash and discovered that the entire blower assembly was packed with tissue paper, where the rodent had made a nice and comfortable nest.

It may sound gross, but an animal carcass in the car would definitely get a bit more ripe when it got hot out, and that kind of fits the description of what you are experiencing.
posted by quin at 5:05 PM on May 23, 2007

Are there any damp areas on the floorboards/firewall? A leaking heater core can drip antifreeze into the cabin, it can smell even in small amounts. The padding on the firewall can soak up this stuff and it will linger for quite some time. Have you used your heater/defroster(or defogger) lately? There's usually no pressure coming into the heater core until it's turned on, just liquid sloshing in it.
posted by IronLizard at 5:42 PM on May 23, 2007

Would a dog help?

I've never tried this, but perhaps a curious dog of the right type could sniff out the source assuming it is organic; e.g., a dead rodent.
posted by Kevin S at 5:51 PM on May 23, 2007

An animal carcass in the ventilation system could also dry out and stop smelling, then get dampened with A/C condensation and start smelling again.
posted by flabdablet at 8:15 PM on May 23, 2007

My car also smelled badly. Turned out there was leak which caused water to fill up inside of the spare tire well. Sick.
posted by |n$eCur3 at 10:07 PM on May 23, 2007

I have a '95 Corolla, and this and other Corolla's I have had have had the following smells(mostly already mentioned):
-a mouse got into the blower motor (for the heating/cooling system)-this was noticed more by the fan sound than the smell, but I have no idea how it got in there
-catalytic converter does give off different smells from time to time- kind of a sulfury smell
-stagnant water in the wells in the trunk-not the spare tire well but the ones on the sides
-turning the AC off often produces a weird smell for a few minutes
-radiator core leaking (the part inside the compartment, not the big radiator)
-package of sausages fell out of the grocery bag and hid under the seat for 3-4 weeks... this was the worst

Radiator fluid has a distinctive odor. Open up a bottle of antifreeze and see if that's the same smell.
posted by MtDewd at 6:49 AM on May 24, 2007

-radiator core leaking (the part inside the compartment, not the big radiator)

It's called the heater core.
posted by IronLizard at 7:48 AM on May 24, 2007

Just had my heater core go out, and my car ('95 chevy) was suddenly filled with a smell, but it wasn't remotely sweet. It smelled like horrible rotten fish. The whole thing kind of confused me because I thought it couldn't be antifreeze because it wasn't sweet.

It was explained to me that since I didn't do things like flush out the coolant ever, my antifreeze had probably aquired that horrible stench due to its age.

So don't rule out the possibility of it being antifreeze, just because it doesn't smell sweet. Mine definitely had an unberable stinky rotten smell.

I'm no mechanic, but I had the same situation where the smell would come and just go away, and then months later appear again. Other symptoms I had leading up to the heater core failure were that I leaked antifreeze and had to have it refilled when I got my oil changed. Of course I had related issues where the heater wouldn't work & the car ran hot while the antifreeze was low. This went on for 1.5 years before the car finally just broke down. So maybe your heater core is working on breaking.

The heater core is in or around your dashboard / glove compartment. In fact, everything in glovebox was soaked when it broke. Mine cost about $350 to fix.
posted by FortyT-wo at 8:14 AM on May 28, 2007