Strange fumes in my ML55.
Discussion
Wonder if anyone can point me in the right direction here? This small issue has shown itself pretty much since I bought the ML55 a couple of years ago. When I seriously floor it, the cabin is very quickly filled with a strange, possibly sulphurous type of smell. It is completely different from the exhaust smell and is present whether the windows are up or down. I did some searching a while ago and catalytic converter was mentioned?
Seems unlikely that you'd have a bad enough exhaust leak for it to happen that quickly (especially at speed) without the sound being obvious.
Do you have any oil leaks under the bonnet? A crank case pressurisation problem leading to combustion gases blowing into the engine bay might show up as oil leaks from the dip stick tube etc. I'd expect that to produce a recognisable exhaust smell though.
The smell of a burning clutch is quite distinctive and not particularly sulfurous but I wonder whether you may have a slipping clutch or something like that.
Do you have any oil leaks under the bonnet? A crank case pressurisation problem leading to combustion gases blowing into the engine bay might show up as oil leaks from the dip stick tube etc. I'd expect that to produce a recognisable exhaust smell though.
The smell of a burning clutch is quite distinctive and not particularly sulfurous but I wonder whether you may have a slipping clutch or something like that.
Geabox oil certainly has a strong smell but I wouldnt describe it as sulphurous. The two most common causes of a sulphur smell are, the cataytic convertor whilst warming up or an overcharging battery, although if it was an overcharging battery it would have died completely long before two years.
Thanks for all the replies. Maybe my "sulphurous smell" was not strictly correct? It is an unusual smell and unlike any other I have detected from a car and certainly way different from oil or exhaust types of smells.
The car passed its "MOT" with no issues last year and the exhaust is in good shape. I changed the transmission fluid (it is an auto)a couple of months after I purchased it and used the Mercedes fluid. The battery looks quite old but works well and as an additional aid, I have it on the Citek conditioner every night - hopefully this is not causing any overcharging?
I did have a small "oil" leak earlier but this turned out to be power steering fluid and I fixed this by changing the reservoir and seal.
One other small observation, and again it happens under hard acceleration, is a kind of chirping or higher frequency whirring coming from the engine. This is most noticable with the windows down. Almost like one of the pulleys protesting a little?
The car passed its "MOT" with no issues last year and the exhaust is in good shape. I changed the transmission fluid (it is an auto)a couple of months after I purchased it and used the Mercedes fluid. The battery looks quite old but works well and as an additional aid, I have it on the Citek conditioner every night - hopefully this is not causing any overcharging?
I did have a small "oil" leak earlier but this turned out to be power steering fluid and I fixed this by changing the reservoir and seal.
One other small observation, and again it happens under hard acceleration, is a kind of chirping or higher frequency whirring coming from the engine. This is most noticable with the windows down. Almost like one of the pulleys protesting a little?
Edited by el romeral on Monday 5th August 09:45
Smells like eggs? Sounds to me as though your catalytic converter needs a good burn at high temperature - your 55 just doesn't appear to be running for a sufficient length of time / high enough revs to get the cats to get hot enough.
I'm sure that someone else will have a more eloquent way of describing this...?
I'm sure that someone else will have a more eloquent way of describing this...?
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