will a clogged catalytic converter create a rotten egg smell?

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If a cat clogs, does it have this "rotten egg" smell? or is just carbon build up? Our Tracker does still have this smell but the performance of it is fine? op
 
i think so, i remember being 5 and driving with my uncle and smelling something like that and he said it was a catalytic converter... but then again he could have just been covering up.
 
My best guess is that that sulfur smell has to do with operating temperature of the cat. All I know for sure is that early 3-way cats (during the late '80s) produced a pronounced rotten egg smell before the operating temperature was reached. This was no reason for concern. I sometimes smell a very faint whiff of sulfur from my car's tailpipe.
 
google says rotten egg smell is from too rich a fuel mixture running thru the catalytic converter.

the rotten egg smell is hydrogen sulfide/disulfide I think. I don't think fuel has much sulfur in it, wouldn't say it's considerable, but you probably need very little sulfur to form enough H2SOx to smell it. Engine operating temp being too cold combined with rich fuel mixture passing uncombusted fuel and not enough oxygen to a not hot enough cat is probably the mechanism for the rotten egg smell. It seems like this smell is not a symptom of a clogged or plugged cat. If the cat were plugged, there is a very noticable performance and economy drop, like not being able to get over 2k or 3k rpms because of exhaust backpressure.

[ November 14, 2005, 02:22 PM: Message edited by: 1 FMF ]
 
I remember the first Camry's all had that smell. A workmate had to buy a 'deordorizer' gas additive at the auto store since Toyota had no solution. Maybe your problem is related to a brand of gas. You might try another.
 
On our fleet of cabs the cats start smelling like this every 100k miles. We either run a line through it or put a new one on, that usually cures it.
 
Over here fuel does have sulphur in it. Depending on the brand and the grade it can be up to 500 parts per million. I think Shell Optimax has much higher sulphur levels than Bp Ultimate(both 98 octane).

Diesel fuels are also having a reduction in sulphur. This will allow the use of high tech/ efficiency motors.
 
quote:

Maybe your problem is related to a brand of gas. You might try another.

Maybe that can or used to be true but this explanation sounds like something the stealership would say
nono.gif
. My 05 5 speed Vibe now has 9 k miles on it and I have been patient with said problem. I use a variety of name brand fuels ( often 89 octane) Some days are more pronounced than others but I am now insisting that the dealer replace the cat. According to the dealer this part is in short supply. It appears that I am not the only one
dunno.gif
 
President Bush signed an executive order following Katrina where restrictions on gas quality and sulfur content were lifted "temporarily".

I think my cats are clogged as well because I smelled heavy rotten egg odors a few months ago. Now the cat is just clogged (burning red hot) creating nasty burning smells in the cabin and plugging up the car's power.

Everyone is saying it's a leak on that bank (intake/exhaust) or that my camshaft timing is off (Ford 4.6L SOHC V8), or that I'm running lean due to my tune.

I slapped on new O2 sensors but it didn't solve anything.

it also happened when I started using 87 octane fuel.
 
Fuel quality didn't drop. All they did was play with volatility and.......
http://www.epa.gov/compliance/katrina/waiver/index.html
http://www.epa.gov/katrina/faqs.htm#11

Rotten egg smell isn't caused by carbon buildup or by a clogged cat. Actually, its proof that your cat is working. At lower temps, sulfur buildups/coats the convertor. When it gets hot enough, it'll burn it off and stink. Some cars are more sensitive to fuel then others.
If it becomes a common smell regardless of gas station, then you're probably running rich(building up that sulfur quicker). Get a tuneup.
 
A couple of my Nissans stunk plenty of times.
Could it be a 'cheap' OEM cat? or some other issue?
It wasn't permanent.
The smell did go eventually away(after break in?, after moving(different gas station?, after......).
 
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