petrol cars - combustion products

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Wed 17 Apr 2013 16:56
petrol cars - combustion products - derk1

the smell of petrol has changed over the last few years.The smell of exhaust is notably different.

Is the addition of alcohol the cause of this? In complete combustion will give aldehydes which so far as I know are not tested for in emissions testing.Aldehydes are carcinogens.Has anyone come across hard information about this?

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Wed 17 Apr 2013 17:06
petrol cars - combustion products - jc2

Catalysts are the main reason.

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Wed 17 Apr 2013 17:08
petrol cars - combustion products - unthrottled

Well the sulphur level has dropped to negligible levels in the last few years-and sulphurous compounds can be pretty noisome. EN228 defines ranges for the different constituents of petrol, rather than a defined make-up. Worryingly, it doesn't specify a calorific value...

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Wed 17 Apr 2013 17:31
petrol cars - combustion products - RT

Incomplete combustion will be noticeable by high readings of those things that are measured, eg CO and Nox.

I agree with the above - catalytic converters and ultra-low sulphur fuel.

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Wed 17 Apr 2013 17:54
petrol cars - combustion products - unthrottled

Catalytic converters have been (effectively) mandatory on new cars since 1992. You can remember what petrol smelt like twenty years' ago??

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Wed 17 Apr 2013 20:19
petrol cars - combustion products - MrEckerslikefromRamsbottom

Catalytic converters have been (effectively) mandatory on new cars since 1992. You can remember what petrol smelt like twenty years' ago??

Twenty years? How about 40 years? I can remember what it tasted like as well... I haven't tried that since. Surprising what sticks in your mind whilst you forget other things in your past..That was working on Minis and not being able to afford the correct tools....

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Wed 17 Apr 2013 17:56
petrol cars - combustion products - craig-pd130

The different smell from exhausts is simply because of better fuelling that's better matched to engine demand, thanks to the near-blanket use of efficient injection systems and catalytic converters.

It's very nostalgic to follow a classic car (or a pre-92 car without a cat). I can assure you that my 70s Suzuki 2-stroke triple still smells pretty much the same as they always have!

Edited by craig-pd130 on 17/04/2013 at 17:57

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Wed 17 Apr 2013 18:57
petrol cars - combustion products - Andrew-T

Is the addition of alcohol the cause of this? Incomplete combustion will give aldehydes which so far as I know are not tested for in emissions testing.Aldehydes are carcinogens.

If aldehydes are a serious cancer worry, we had all better stop drinking so much ethanol in our regular tipple. I think acetaldehyde - the partial oxidation product of ethanol - is one of the important congeners in most wines?

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