V6 Diesel software update recall

[Petrol Pete]

Don't you just love the simplicity of a Diesel engine...

 

[igk1]

Are there legal consequences of refusiong to have the update done? The DVSA leaflet states that you may commit an offence by not promptly acting on a safety recall.

 

[rtfm]

I wish I had not taken my GLC in for the Euro 6 emissions recall earlier this year. Fuel consumption is at least 10% worse in all modes. In city use it is more like 20% worse off.

 

[martyz]

And you won't be able to take a diesel car/van/truck into Bristol city centre in two years time,with many cities to follow suit.
The VW scandal has red flagged diesels as not an option for many now.And everybody thought they were going green by getting
massive gains in fuel consumption, oh dear how the people are mislead

 

[wongl]

The software update is aimed at reducing NOx so more EGR and Adblue operation , so more wear for these emission systems .

With even more egr inert gasses gives more incomplete combustion through less oxygen = even more soot for the dpf to deal with along with reduction of drivability .

The EGR is intented to limit the oxygen going into the cylinder thereby requiring less fuel to achieve ‘isotropic’ combustion (lambda = 1.2) to allow the engine to run lean without damage.

So more EGR should allow the engine to run even leaner with damage and I don’t agree that it will cause ‘even more incomplete combustion’. By default, an isotropic combustion cycle with lambda at 1.2 is the ‘most complete combustion’ point of an engine.

 

[Bellow]

The EGR is intented to limit the oxygen going into the cylinder thereby requiring less fuel to achieve ‘isotropic’ combustion (lambda = 1.2) to allow the engine to run lean without damage.

So more EGR should allow the engine to run even leaner with damage and I don’t agree that it will cause ‘even more incomplete combustion’. By default, an isotropic combustion cycle with lambda at 1.2 is the ‘most complete combustion’ point of an engine.

Ehhh?

 

[Mactech]

Ehhh?

Oh! Come on! Promise me you knew all about this...
https://www.tandfonline.com/doi/abs/10.1080/713712911

I can even pronounce some of the words in this article! (Like 'the' and 'rare')

 

[grober]

W218 optional ECU software updatr

 

[Bellow]

Oh! Come on! Promise me you knew all about this...
https://www.tandfonline.com/doi/abs/10.1080/713712911

I can even pronounce some of the words in this article! (Like 'the' and 'rare')

Talking of Lambda as he was, he is referring to stoichiometry and even then the numbers are suspicious. Lambda = 1.2 is 80% air utilisation - a full load condition. My understanding is that modern day diesels run (quite a bit) leaner than that to enjoy the benefit of lower combustion temp and thus lower heat loss.

If he wants to stray into terms associated with thermodynamics, the ratio of specific heats is the term required to understand why EGR is employed.

 

[wongl]

It has been a while since I worked on engine management system, last time was back in 1994 when we worked on the early pizzo-injectors with MB.

I am sure back then we were coding the ECU to achieve Lamda to converge to 1.2. It was a single cylinder Diesel engine for experimental use in the lab.

Maybe things have moved on since?

 

[Gazwould]

The EGR is intented to limit the oxygen going into the cylinder thereby requiring less fuel to achieve ‘isotropic’ combustion (lambda = 1.2) to allow the engine to run lean without damage.

So more EGR should allow the engine to run even leaner with damage and I don’t agree that it will cause ‘even more incomplete combustion’.

More incomplete combustion for sure , with egr out , fresh engine oil stays cleaner for longer .

 

[TeddyRuxpin]

I had mine done today during a service. They kind of slipped it in when briefing me, trying to sell it as a good thing, and didn’t say that it was voluntary. and it was only when I was going to collect the car that I remembered this thread and swore a lot. I called up the dealer and they said it had no impact on power.

When I got back in the car, I found the letter (attached).

Still, I don't mind if the car is more environmentally-friendly.

On the way back, I couldn't tell any difference in performance, but then it was always going to be just a few percent in power reduction, if any. As I have a higher milage vehicle, I hope it's not going to put a lot more stress on DPF and EGR etc, or a detrimental impact on economy.

 

[TeddyRuxpin]

By the way, my car doesn't have AdBlue.

 

[Deleted member 6183]

By the way, my car doesn't have AdBlue.

I doubt that normal people will have any issue with the adjustment.

 

[TeddyRuxpin]

Not sure which category of people I fall into though

 

[Deleted member 6183]

Not sure which category of people I fall into though

Well, if you have to ask

 

[Mactech]

Well, I solved the problem of wether to have the software update done or not in a rather novel way.
I sold the car!
It goes next week to be replaced by something which has the same speed, space and luxury, is 3.5 years younger and does an additional 50% more miles to the gallon.
....and cost less than £1k to change.
I see that as being environmentally responsible......to me!

 

[TeddyRuxpin]

Could be another issue, or too early to say, but I think my MPG might be down around at least 10% too...

 

[TeddyRuxpin]

By the way, has anyone else had this that doesn't have an AdBlue car?

 

[Bobby Dazzler]

Well, I solved the problem of wether to have the software update done or not in a rather novel way.
I sold the car!
It goes next week to be replaced by something which has the same speed, space and luxury, is 3.5 years younger and does an additional 50% more miles to the gallon.
....and cost less than £1k to change.
I see that as being environmentally responsible......to me!

So what did you buy?