SL/R129: What is that rotten egg smell?
Thread Starter
MBWorld Fanatic!
Joined: Jul 2003
Posts: 1,181
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From: Abbotsford, BC, Canada
1999 SL 500 & 2011 E 550 4Matic
What is that rotten egg smell?
After a dozen runs of hard acceleration, There seems to be an odour comming from ther exhaust.
Some one once posted that it is had something to do with too rich of a fuel mixture and somehting to do with the the catalitic converter.
Can any one explain this better to a non mechanical guy like me?
Is it bad for the car? Should I not do the quarter mile + flat outfor fun time after time like that?
Should I report it at the next regular service?
Some one once posted that it is had something to do with too rich of a fuel mixture and somehting to do with the the catalitic converter.
Can any one explain this better to a non mechanical guy like me?
Is it bad for the car? Should I not do the quarter mile + flat outfor fun time after time like that?
Should I report it at the next regular service?
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some
Originally Posted by ChrisB
After a dozen runs of hard acceleration, There seems to be an odour comming from ther exhaust.
Some one once posted that it is had something to do with too rich of a fuel mixture and somehting to do with the the catalitic converter.
Can any one explain this better to a non mechanical guy like me?
Is it bad for the car? Should I not do the quarter mile + flat outfor fun time after time like that?
Should I report it at the next regular service?
Some one once posted that it is had something to do with too rich of a fuel mixture and somehting to do with the the catalitic converter.
Can any one explain this better to a non mechanical guy like me?
Is it bad for the car? Should I not do the quarter mile + flat outfor fun time after time like that?
Should I report it at the next regular service?
its your cats man.
after a while you wont have any power and it will smell like crap always.
better change them!
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Joined: Mar 2005
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From: Adelaide, Australia. Formerly Bristol, UK.
1998 SL 600 ///AMG. 1997 SL 320. 1999 SLK 230K. 2001 BMW R850.
Originally Posted by HLG600
Mark's right, that smell correlates to a problem with your catalytic converter. But don't worry, you now have an excuse to put in higher flowing ones. 
Thread Starter
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From: Abbotsford, BC, Canada
1999 SL 500 & 2011 E 550 4Matic
Originally Posted by RedMongoosE
its your cats man.
after a while you wont have any power and it will smell like crap always.
better change them!
after a while you wont have any power and it will smell like crap always.
better change them!
You guys seem to imply that "free-er" flowing catalytic converters will improve performance.
Does that mean other than MB equipment?
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Joined: Nov 2001
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From: Fort Worth, Tx
97 SL500
The smell doesn't necessarily mean you have bad cats, it can be caused by high sulfer content in the fuel. I wouldn't run out and change the cats unless you are experiencing some of the "other" symptoms that they are going bad like reduced performance or worsening gas mileage.
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From: Abbotsford, BC, Canada
1999 SL 500 & 2011 E 550 4Matic
Originally Posted by Lincoln
I wouldn't run out and change the cats unless you are experiencing some of the "other" symptoms that they are going bad like reduced performance or worsening gas mileage.
Performance is fine.
Under "normal" or reular lead foot driving there is no smell.
The gas mileage is fine also.
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From: Toronto
1998 E320, 1994 320 SL,2000 Ford F 150.1997 Gixxer 1100
Originally Posted by Lincoln
The smell doesn't necessarily mean you have bad cats, it can be caused by high sulfer content in the fuel. I wouldn't run out and change the cats unless you are experiencing some of the "other" symptoms that they are going bad like reduced performance or worsening gas mileage.
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Thread Starter
MBWorld Fanatic!
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From: Abbotsford, BC, Canada
1999 SL 500 & 2011 E 550 4Matic
Originally Posted by kerrypacker
Under major power take offs I get the smell also and my cats are brand new free flows just done last August. My opinion is its the sulphur in the gas.
Both times I had gone nuts doing nearly back to back 0 to 125 mph maximum acceleration runs. Say 10 runs of that punctuated only with with foot to the floor cruising arround a large park property between the runs.
Very heavy driving both times over a 30 to 45 minutes span of time. Pretty smelly at the end of that punishing treatment!
From what you say, I would guess that it was the driving & maybe something to do with the quality of gas in Canada.
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mercedes gl450
I just took my 2014 GL to the dealer for the bad smell. There is an article about something leaking from the engine. They had to reveal it and Ionia the interior of the car. It's a known problem now. I am just curious if I have been driving my car for a year with deadly fumes in the cab. Anyone knows?
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From: Scotland, UK
1998 R129 SL500
Cars prone to short journeys, low rev and Low mileage use, if given some right foot heavy use now and then will smell a bit. As already said though, unless other symptoms are experienced or it is smelling bad all the time, I would not be rushing out to buy new cats!!
