Mercedes bluetec has been around for 10 years in the U.S. and I've not heard of any complaints.

If only VW had done the right thing in the beginning we might have expected the same outcome.

Hopefully the buried EGR valve is not required so often and will last much longer.......assuming there is one still.

?

What was the outcome of the USA's Federal Investigation into the Mercedes BlueTec system and emissions, 

did they find that the Ad-blue tank was large enough and the set up actually reduced the NoX emissions all the time they were required to and not just at the temperatures that the EU Emissions testing required them to?

(The VW Group vehicles Adblue tanks in the US were not large enough, hence the need to have Defeat Devices or install much larger tanks, 

or have customers filling up more often.)

http://en.wikipedia.org/wiki/BlueTec

Edited 16 October, 20169 yr by Offski

SCR is yet another expensive system to go wrong and needs regular infusions ad blu (all be it cheap at the moment until HMGov realise the more miles you do the more you use? nice way to tax high milers with efficient engines?)

 

yet another restriction in the exhaust system strangling performance and reducing fuel economy (not as bad as DPF though )

 

all these systems are great when the car is under warranty,

 

But how expensive is it when it goes wrong and SCR cat needs replacing?

 

There is no extra restriction in the exhaust.

There is no additional SCR cat.

Edited 16 October, 20169 yr by Llanigraham

There is 20% VAT on Adblue as i understand, and the import tariff is 5.8% into the UK, 

but that is just from looking at the list of various tariffs and sales taxes for Ad-blue around the world.

Edited 16 October, 20169 yr by Offski

There is no extra restriction in the exhaust.

There is no additional SCR cat.

so which cat is used, this diagram clearly shows a separate CAT

 

^^^

It shows the exhaust, and not many just have a DPF and no middle or rear box. or even more than that.

Not many Euro 6 emissions diesels come with a PDF and a straight through exhaust system.

 

Edited 16 October, 20169 yr by Offski

There is no extra restriction in the exhaust.

There is no additional SCR cat.

Then what does SCR stand for, Oh yes Selective Catalytic Reduction.

That's 3 obstructions before it gets to the silencer.

Oxidation Catalytic Converter

Diesel Particulate Filter

Diesel DeNOx Catalyser

They are not restrictive or strangling performance particularly, they are required to reduce NoX so it is going to be done the way it is with SCR or in some other manner.

 

If you don't want a Euro 6 emissions diesel but want a diesel maybe go back to Euro 4 ones and miss out Euro 5's with DPF.

If you want petrol's then maybe best buy new soon because particular filters are coming to them soon enough.

 

If you want petrol's then maybe best buy new soon because particular filters are coming to them soon enough.

 

"Gasoline Particulate Filter" likely to be simpler and much more reliable as the hotter petrol combustion temperatures mean usually only passive regeneration will be required. I don't think GPFs will appear on every engine - it's direct injection petrol engines that produce more particulates

Edited 16 October, 20169 yr by bigjohn

The SCR system has some pretty expensive components involved and they do go wrong, quite frequently.

 

The NOx control unit is a common issue & works out around £400, plus the software update required to go with it and the necessary and legally required test drive and DPF regeneration that is obligatory to reset the system after a fault to ensure the system is operating correctly. The regen and test drive necessary to clear the threat lamp can be a long winded affair and is all chargeable to the customer.

 

Adblue injectors and lines suffer with crystallisation issues & Adblue tank sensors are also becoming an issue.

 

Personally i'd give one of these EU 6 diesels a miss if I valued my bank balance.

It is just as well that consumer law will be on the side of the purchaser if there are Fundamental Design or manufacturing faults or materials and the manufacturers are selling vehicle not fit for purpose.

Warranties are going to be rather important and then the experiences of qualified technicians like yourself and Independent Experts in Motor Vehicle engineering.

 

I am sure Dealership Employees or the Warranty Provider might like to claim that it is all chargable to the customer, 

obviously if it is they will be getting reimbursed where the Manufacturers Warranty covers the faults.

Obviously it is not user error where it is a systems failure.

Edited 16 October, 20169 yr by Offski

Then what does SCR stand for, Oh yes Selective Catalytic Reduction.

That's 3 obstructions before it gets to the silencer.

Oxidation Catalytic Converter

Diesel Particulate Filter

Diesel DeNOx Catalyser

 

Well according to the diagram above there are only 2, so I stand corrected, although from other comments it looks like the Yeti might have a combined unit, so it may actually only be one. 

And the "Catalytic" in the acronym SCR I understand to relate to the chemical reaction that occurs following the injection of the urea based fluid into the system, where the urea acts as a catalyst.

Skoda claim the exhaust system is made of 'stainless material' etc - for info

It can be exhausting being an exhaust, having to take on very high temperatures, heavy moisture, dust, small stones flying up from the wheels, shocks and vibrations. At ŠKODA, we make our exhaust systems from high quality stainless material or a combination of it and double-sided aluminiumised sheet, guaranteeing your exhaust doesn’t run out of puff.

A VW clean diesel technology videos along the same lines -

Edited 17 October, 20169 yr by Ryeman

Well according to the diagram above there are only 2, so I stand corrected, although from other comments it looks like the Yeti might have a combined unit, so it may actually only be one. 

And the "Catalytic" in the acronym SCR I understand to relate to the chemical reaction that occurs following the injection of the urea based fluid into the system, where the urea acts as a catalyst.

nope, the urea is a reductant which reacts with the NOx in the presence of a catalyst in the SCR CAT

 

http://alternativefuels.about.com/od/researchdevelopment/a/scr.htm

 

SCR Catalytic Converter: This is where the conversion happens. Exhaust gases and an atomized mist of DEF enter the converter simultaneously. Together with the catalyst inside the converter, the mixture undergoes a chemical reaction that produces nitrogen gas and water vapour.

https://en.wikipedia.org/wiki/Selective_catalytic_reduction

Every day's a learning day.

Not specifically adblue but the negativity around diesel, forthcoming additional taxes for diesels, dmf, egr and dpf issues have all put me off buying another diesel.

 

So we run 4 family cars all of which were turbo diesel and have been for many years.

 

Now 3 of the four are turbo petrol and when the 4th one is replaced that will be petrol too.

 

Can't see me ever having a diesel again.

 

Lee

I'm glad that I've got a couple of more years left with my diesel Yeti as I love the combination but when the warranty is up I shall probably move to petrol particularly as I will have fully retired by then and won't be commuting.

Having other cars which are petrol it is nice having a diesel for something different.

My first diesel was a Vento 1.9 which was a very nice car. With the Yeti I'm now on my 7th diesel so it will be a sad day when that goes.

I'd rather have Adblue rather than the problem surrounding the Euro 5 engines and once you have done your first refill it's not a problem at all.

Edited 17 October, 20169 yr by VAGCF

We've got a car each (an indulgence) and my ideal second one would now be a BEV in a couple of years when increased production bring unit costs down.

Massive grunt off the line would be fun )))

for me the actually cost and filling with adblue is not the issue

 

its the cost of the system both in the initial purchase price of a diesel (circa £2k last time I looked at the premium of a diesel of a same output as a petrol) and the cost of it goes wrong, VAG seem to be charging some outrageous costs for items failing just out of warranty at relatively low mileages looking at threads on here

 

first EGR, then DPF, now adblue, what next? and at what cost

 

and that is regardless of car / engine manufacturer

for me the actually cost and filling with adblue is not the issue

 

its the cost of the system both in the initial purchase price of a diesel (circa £2k last time I looked at the premium of a diesel of a same output as a petrol) and the cost of it goes wrong, VAG seem to be charging some outrageous costs for items failing just out of warranty at relatively low mileages looking at threads on here

 

first EGR, then DPF, now adblue, what next? and at what cost

 

and that is regardless of car / engine manufacturer

SCR should solve the EGR problem and premature DPF fouling (assuming the SCR equiped cars don't have a smaller DPF) so a net positive.

The use of the EGR to control combustion temps (NOx) was an abortion of a system in comparison to SCR/DEF injection which the Merc/BMWs have had for years........

(remember 'they' couldn't work out how VW achieved the U.S. pass without it.......they couldn't, they cheated)

Things are only going to get harder from next year though .........something the manufacturers are fighting against

SCR should solve the EGR problem and premature DPF fouling (assuming the SCR equiped cars don't have a smaller DPF) so a net positive.

The use of the EGR to control combustion temps (NOx) was an abortion of a system in comparison to SCR/DEF injection which the Merc/BMWs have had for years........

(remember 'they' couldn't work out how VW achieved the U.S. pass without it.......they couldn't, they cheated)

Things are only going to get harder from next year though .........something the manufacturers are fighting against

 

Is it the EGR that causes premature DPF fouling? - I thought the EGR/cooler cooled exhaust gasses and sent this back into the air induction to reduce oxygen content

 

Presumably once past the EGR on the exhaust the first system is the DPF followed by catalyst/SCR etc?

Edited 18 October, 20169 yr by bigjohn

The EGR is a crude tool used to manage combustion temperature spikes resulting in increased NOx emissions .

It does it by directing an amount of exhaust gas through a cooler then back to the inlet to lower the temperature - a very dirty (component fouling) inefficient control method.

The SCR system allows the greater power efficiency (and economy) with its greater NOx output but deals with that post DPF (90% reduction).....and should eliminate the EGR valve/cooler. ))))))

The DPF benefits from the fact that the constant high combustion temperature means greater burning efficiency thus significantly less particulate matter for the DPF to deal with, extending its life (unless they reduce its capacity to save weight?).

Perhaps the advent of SCR has made the 5 year extended warranty achievable due to longer term reliability.

Maybe it'll be standard in time.

https://vwconnect-marketing.extendcloud.com.au/MHCwa/msg/em.aspx?i=PCM_PROD&id=320FF3900F8F4ADFA1AF59349A188C7B

Edited 3 November, 20169 yr by Ryeman

Is there longer term reliability or just not as good sales as they want, so more marketing is required.

Hopefully they will have both improved reliability & residuals and get good sales from selling good value vehicles.