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alexturner
7th September 2011, 10:50 PM
Hey guys,

Off to the Simpson on Friday and I noticed tonight that my exhaust seems a little smokey. I had a friend drive behind me who told me it was a greyish smoke. I pulled over to inspect and ran the car up to rev and inspected the smoke with my torch. It seems to be a whitish smoke but it's by no means excessive - at the time the engine was cold.

I've checked the engine bay - no water loss, no oil in the bay, head gasket surrounds seem to be in good nick. Is this problematic or am I over reacting?

Thanks guys,
Alex

Fraz
8th September 2011, 12:29 AM
not sure if diesels do it as much (or at all), but when a cold petrol engine revs up there is steam in the exhaust, due to vapours cooling when the engine shuts off and then heating again with the hot exhaust.. and the torch will change the colour of the smoke anyway

wait till morning and a warm engine before you check it again

rainman
8th September 2011, 08:23 AM
Diesel smoke will look a bit white at night with a light shining on it. When is it smoking worst - idle, off idle, accelerating, under load uphill, low boost? You're injector pump might need a little fiddling with, but I wouldn't touch it now given that you're off on the big trip tomorrow! It's probably (hopefully) just a tuning issue.

How many kilometres are on your engine?


James.

LowRanger
8th September 2011, 08:24 AM
Alex

Night time is not a good time to check smoke from a diesel.
The smoke always seems more noticeable under lights.Check it again in the daylight,you will probably find it is normal,and you are being paranoid due to the fact that you have a big trip coming up.

Wayne

LoveMyV8County
8th September 2011, 08:32 AM
White smoke that dissipates easily = moisture
Blue/grey smoke that hangs around = oil (can usually smell the burnt oil too).

Following on from what Fraz says - if the surrounding air is cold the water that is produced by burning hydrocarbons (diesel, petrol, LPG) will condense as it comes out the exhaust. This is exacerbated when the mixture is enriched on startup.

Once the engine and exhaust system have warmed up it should reduce and as the outside air warms should become invisible. If this does not happen you could have a head gasket leak (the exhaust may also become speckled with water droplets).

hth
chris