Mercedes E class 2017. 250d - Intermittent smoke greyish from exhaustt

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Tue 16 Feb 2021 19:52
Mercedes E class 2017. 250d - Intermittent smoke greyish from exhaustt - Melly Goldsman

My sister/family bought the above car, pre-registered.

FSH by MB

Current miles, 20k.

Driven 500 miles since last service in the summer, August if I recall correctly.

Car is out of warranty.

Car had a knox sensor replaced FOC by MB year ago when it went wrong.

Something about a emissions recall was done last service, FOC.

Last 2/3 months they've noted massive clouds of whitish, greyish smoke even when the car has warmed up. No warning lights etc and no smells of fuel, etc. Car is not losing any water.

What they have noted the last couple of weeks is that this scenario may happen on shorter drives of about 5/8 miles and especially if the car has been revved a few times, IE kickdown.. Often, stopping the car and restart soon get rid of the smoke.

With lock-down they rarely drive the car but it is not moisture as there is too much of it even when the engines hot. The fault is not readily replicated.

Looking around the web, could it be a faulty fuel injector IE stays open for longer after hard acceleration?

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Tue 16 Feb 2021 19:59
Mercedes E class 2017. 250d - Intermittent smoke greyish from exhaustt - Heidfirst

Could well be wrong as I have no experience of MB but it sounds to me like a DPF trying to regenerate.

Edited by Heidfirst on 16/02/2021 at 20:00

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Tue 16 Feb 2021 20:33
Mercedes E class 2017. 250d - Intermittent smoke greyish from exhaustt - daveyjp

Doing 5,000 a year and 5-8 mile trips really isn't good for a diesel.

They need to get out and do some decent miles and consider if it is suitable for their use pattern.

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Wed 17 Feb 2021 14:59
Mercedes E class 2017. 250d - Intermittent smoke greyish from exhaustt - madf

Doing 5,000 a year and 5-8 mile trips really isn't good for a diesel.

They need to get out and do some decent miles and consider if it is suitable for their use pattern.

"Doing 5,000 a year and 5-8 mile trips really is a good way for fouling up the fuel injectors, the catalyst,the EGR valve and TOTALLY the wrong choice of fuel...

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