Grey-ish/white smoke on accelaration...?

[ramer]

I have an '07 plate E320 V6 diesel estate with about 75K miles on the clock, Mercedes serviced from new.

On firm/hard accelaration there is greyish-white smoke, (sometimes a lot with hard accelaration). Sometimes get small amount of white smoke on start-up. Runs smoothly, and really love the car, but perturbed by this smoking - which seems to have come on in the last 6-9 months.

MPG is around ~48/gallon on a motorway run at 65mph, and around 28 around town. Any idea what the reasons might be for the grey/white smoke, and is there something I can do to about it?

Many thanks.

 

[panason1c]

The white smoke on start up (more prevalent on short trips) is probably condensation in the exhaust system burning off during these cold, frosty mornings, if you are not losing any coolant then i would guess you have nothing to worry about.

 

[ramer]

The white smoke on start up (more prevalent on short trips) is probably condensation in the exhaust system burning off during these cold, frosty mornings, if you are not losing any coolant then i would guess you have nothing to worry about.

Thanks for the quick reply.

I guess I'm probably more concerned about the smoke on accelaration - I've never had a diesel before, and never had a car that's smoked like this either...!

Thanks.

 

[panason1c]

If you drive a diesel fairly moderately for a while you get a gradual build up of ash in the exhaust system which reveals itself as a cloud of smoke as the ash is blasted out when you eventually boot the car, it looks particularly bad at night when there is a car behind you with headlights on. All perfectly normal!

Take the car for an 'Italian tune-up' and afterwards you will see that the smoke is dramatically reduced.

Welcome to the world of diesels. (-:

 

[ramer]

If you drive a diesel fairly moderately for a while you get a gradual build up of ash in the exhaust system which reveals itself as a cloud of smoke as the ash is blasted out when you eventually boot the car, it looks particularly bad at night when there is a car behind you with headlights on. All perfectly normal!

Take the car for an 'Italian tune-up' and afterwards you will see that the smoke is dramatically reduced.

Welcome to the world of diesels. (-:

Hah! Interesting point, rarely push the car above 75 to be honest, and only then for 10 minutes at a time maybe. Even at 75 the revs are low-ish - what sort of rev level are we talking about and for how long?

Thanks.

 

[Druk]

Roadspeed is unimportant it's engine revs that's reqd. Hold it in a lower gear and go for a blast at 70 for ten minutes.

 

[ramer]

Given that the engine seems to normally rev at a pretty low level (and given my normally fairly conservative driving style), what is a good target for revs to be at for the 10-1 minutes or so?

Thanks.

 

[panason1c]

Just plant the accelerator hard to the floor from a standstill and keep it there to about 70, or 80 or so, dont worry about the revs reaching the red line........and repeat this 3 or 4 a few times........ you will notice much less smoke after that.