From time to time I’m getting this weird smell inside the car. AC and heater are off. Smell shows up and stays for 10 – 15 seconds and then quickly disappears. It does not happen very often but it's starting to annoy me.

Does anyone know what could be the cause of this smell? Is it possible my clutch is going bad?

 

It could be a # of things...Please be more discriptive.. Does it smell moldy, like a rotten egg, or like something is burning. (like it does after brake fade)

 

I think it's more like a rotten egg. It's a very weird smell and it's hard to describe it.

 

if its an rotten egg smell then your cat might be have a leak

 

+1 Rotten egg smell is your cat.. Could be a cat, or 02 problem....Are you having any driveability problems? How is your fuel consumption?
May want to get your fuel trim and 02's checked out.
Is your exhaust louder or a different tone than usual?

 

lol at first I thought you guys were talking about a cat taking a leak inside my car.

anyways, why would cat-converter or O2 sensors produce this smell?

 

Hydrocarbons and exhaust gasses.

 

clutch smell is unique. I remember that smell very well...Hard to describe but once you smell it you never forget it....Many years ago I had just installed a triple disk high performance clutch in my old 93 Cobra. 200 miles later I had a total of 5 people in the car. One weighing over 250 pounds.(about 800 pounds worth of body plus my teenage sub setup)..Anyways I dropped the clutch and instead of it grabbing it just burnt my clutch...I can't really discribe it, but does it smell like something is kind of burning? Kind of like hot brakes but worse???
Try putting your car in fifth gear give it slight acceleration and slowly letting your foot off the clutch it start to shudder then stall...Don't do this to often it's hard on your clutch btw.


LOL. Just read your post. +1 what maxspeed said.

 

I didn't notice anything strange about fuel consumption. Car seems to run normally. I cant really tell if my exhaust is louder cause my stock muffler recently broke off because of rust and I installed Cattman.

I do have a misfire sometimes but it's due to a bad coil which I'm about to replace.

Also, I've been driving with a broken exhaust (no hangers) about 100 miles on New York roads, do you think this could have caused the problem?

 

same here but with burn smell, gone after 10sec. the car had been driven about 20min b4, what should i look at? my exhaust tone was little louder compare to when i got the car year ago.

 

theoratically=misfire=unburned fuel=rich 02 readings and hydro carbons going thru cat bringing its life expendency down...
Fix your misfire, reset your ecm and allow it to relearn fuel trim "or let it fix itself", and see if the smell goes away...It'll probably be real bad @ WOT the first 100 miles or so then it will probably go away....If this is your problem.......

 

is the SES light on?

 

Ya, I'll definitely do that. Hopefully, that's the problem. I didn't even realize cat-converter could cause smell.

nope

 

free bump........

 

MEOW! Sounds like a cat problem.

 

why don't you just start a new thread, you ganna get much more help that way. No offence, but I think it's better for both of us.

 

cool..........

 

ya..with 26k it must really suck.

 

...........definitely be a cat problem

 

Is there any way I can check that it really is my cat?

 

Gez, how do you have fricken 26k? It's not the stone age anymore!

 

just go ahead and make a new thread. It's not like you are asking which intake is better. I don't think anyone is ganna flame you for your question.

 

hehehe......

 

I honestly haven't seen the "which intake is better" thread. Expect for the "which intake is better thread" followed by 20 flaming orgers. Doesn't sound like a bad thread to me.....I personally am getting sick of the "what looks better" threads myself.
shocks/headlights/foglights/taillights/ racing stripes/20" wings/rims/whatever.
Then again just a few weeks back I had a suspension question, so I can't flame anyone else for asking.
Posting a question in someone elses thread almost never generates any replies.
If your cat was bad you would probably have a mil light..It's probably just smelling because of the extra hydrocarbons created from the unburned fuel. (It's hard to explain how a cat works. But it takes abc molecules and mixes them with def chemicals as they exit your exhaust and thus turns it into a safter ghi, or something like that.).. You probably haven't destroyed your cat yet, but I would get the misfire fixed. More than just potentially ruining your cat and 02 sensors you are causing your cylinder to run hotter and crap to build up on your plugs and valves..

 

Sounds like this smell you are talking about might definitely be a cat problem.

 

so when the cat is not working properly, will it block flow or it will just fail to convert the harmful gases?

 

It can do both.. If what's going thru the cat is more than just the molecules it expects it will create a bad smell and cause it to weaken.. Your cat can go bad because it's not converting into the right molecules..(bad secondary 02 readings)....Or your cat can fall apart from the inside and possibly clog your exhaust.... If it was blocking your exhaust you would know...It would be glowing red, possibly even sparking and you would probably blow a head gasket in no time... Tap on it..If you hear particles rattling around it's probably going bad....I've known people to take their cat off, hollow it out, and put the cat back on....However there is no emissions testing around here and on our Maximas we have a secondary 02 sensor that will set a light if you do this.

 

Ok, I was thinking, you guys are all saying that it’s a cat, but how come it does not always smell, it will only show up like two three times a week and only for about 10-15 seconds?

Also, if it were my cat why does it smell inside, shouldn’t the smell be only outside the car? My exhaust gasses also smell normal.

 

Does it happen after visiting a Taco Bell or White Castle facility?

 

no lol

 

I'm Harold, let me call me Indian friend =]

 

Ok, now back to topic; anybody knows the answer to this:

 

yo DrKlop my fellow staten islander i have this same damn rotten egg smell, a couple times a week only for a few seconds. does yours smell outside the car too? because sometimes mine really smells bad when i get out of the car.

 

Mine shows up only when the car is moving.

 

oh sometimes when i shut the car off and get out it smells...i dunno.

 

I have same smell too, but i know for sure it is the precat. I changed my main cat and smell is still there. Since precats are in front, closer to the vents the smell might be creeping into the cabin. Maybe an aftermarket y-pipe is a good alternative if that is the case for you.
Have you noticed any change in performance?

 

nope, ther's no change in performance.

 

+1...The smell creeps in through the vents. Even if you put it on recirculate cabin air it still gets in.....If it smells like I guarantee it's your cats.......It's probably from your misfire..But if you use different company's fuel or have switched octane you will smell the fuel more often as well. Because of the different additives different companies use, they can leave different contaminants in the exhaust (around 1 or 2 parts per million) and the chemicals in the cat will react differently to them...You say it only happens once in a while..I'm not sure why this is, but that's normal for some reason......Usually it happens more @ WOT because your vehicle goes into "open loop" status and ignores your 02 input readings while adjusting A/F ratio.(It advances your timing and richenes up your A/F ratio for optimal performance)..Then when you start cruising again your car goes into "closed loop" and trys to put adjust your A/F to 14.7:1 ratio. (stoichiometric)...The reason 14.7:1 is where it wants to stay is because your cat will do it's absolute best job at converting hydrocarbons at this mixture..It's really hard to explain..I got $5 that says if you stick with one gas station, the same octane, and fix your misfire that after 200 miles of doing all of this that the smell will probably go away. Here's a link to better explain
http://auto.howstuffworks.com/catalytic-converter2.htm
http://auto.howstuffworks.com/question482.htm
For all the tree hugging Libs out there, that like to pass outrageous laws against people who delete their cats, Here is an interesting link.
http://auto.howstuffworks.com/framed...s2/catalyt.htm

 

Thanks for good info, 5thgenmaxima! You've provided me with pretty much all info I need so far.

 

No problem. I just appreciate the favor returned when I have problems.