Now then, I've noticed in my mirror that, when my car is really pushed and accelerating from a standing start (pretty much at the top of its rev range in 1st) it produces a bit if vapour out of the exhaust - at least I hope it's (unburned) fuel vapour.

It doesn't do this at all times, only when it's launched - I would have thought if it was suffering from a problem that made smoke, it would be present at all times, or when on boost if a turbo problem. Can't replicate this under load or using mid range.

Or have I bought a bad 'un?

Edited 7 December, 201114 yr by j0hn

turbo petrol thing - no problem to worry about

Blue or white?

Blue = oil smoke

White = water vapour

Was it cold? Fair bit of steam from the VRS exhaust on a cold day but I've never noticed it except at standstill.

Aye they do seem to give a puff of smoke when booted, just keep an eye on the oil level.

Typical for direct injected engines, they produce more soot than the DPF-ed diesels.

Three way catalytic converter

Reduction of nitrogen oxides to nitrogen and oxygen

Oxidation of carbon monoxide to carbon dioxide

Oxidation of unburnt hydrocarbons (HC) to carbon dioxide and water

Steam is pretty normal, when car is at standstill water collectas then goes when you launch it.

Or you're in the over fuelling region (designed to keep your turbo cool) and combustion isn't as complete or clean and the cat can't cope with it all What you're seeing is a combination of unburnt fuel and some soot. Nothing harmful for your engine, not good for emissions or fuel economy (but then you're booting it at full revs so....).

Thanks lads, that pretty much confirms what I thought (particularly the last post about overfuelling) but I wanted to ask in case there was a known problem with engines eating themselves.

Never had a turbo petrol car, plenty of TDs and they've all smoked by the time I've finished with them

Edited 8 December, 201114 yr by j0hn

Ive notiched this on mine too,nice to know its nothing to worry about.