OT ish.

[Tim Lamb]

VW have volunteered a payment to owner claimants.

Report in the Times claimed that 400 times more NOx was released using the cheat system than permitted.

Is this likely or some hack misinterpreting figures?

[Dave Plowman (News]

The thing that gets me is London has many many thousands of these diesels with Bosch injection which fiddles the emissions. Yet are exempt from ULEZ charges.

[SteveW]

I also can't see what detriment the owners are claiming for, unless a recall to correct has reduced performance or increased fuel consumption significantly. The authorities have not re-graded these vehicles, so there is no higher VED to pay, no additional Congestion Zone/ULEZ charges and no reason for the resale value to have fallen.

[Colin Bignell]

I had an ambulance chaser type company trying to get me to claim against Mercedes, on the basis that the product had been mis-sold.

[Tim Lamb]

In message [e-mail]>, "Dave Plowman (News)" [e-mail]> writes

Huh! I'm still arguing with London Transport (Darlington) that mistakenly paying £15.00 to drive in North London (ULEZ) should mean they owe me £2.50 rather than me owing them an £80.00 fine!

>

[Tim Lamb]

Kindly don't tell anyone but it is still fitted to my Passat:-)

I've been avoiding main dealer servicing.

[Robin]

OTOH as a London council tax payer I think it's quite neat they have, in effect, a fixed penalty for "Paying Without Due Care and Attention" ;)

[Andrew]

But how many people have had their health affected by VW's cheating ?. These are the *only* people who should get compo, not the whinging vehicle owner.

[Joey]

Of course it has.

Of course the resale value has fallen.

[Richard]

What about compensation for putting up with whinging people who want compensation for everything? There are 8 billion people on the planet despite all the things we're doing which are deemed detrimental to our survival.

[The Natural Philosopher]

probably true.

[Tim Lamb]

I thought the system only altered the injected fuel quantity.

Seems a lot. Does this mean the only diesels meeting the emission level use ad blue?

[The Natural Philosopher]

1. NOX is not a function of fuel quantity alone.
2. Ignition (injection) timing also plays a part.
3. Best fuel economy is from a weak and advanced ignition. Ideal for producing NOx.
4. At the other end of the scale overfuelling produces particulates.

I think not. But that is likely to allow a weaker more advanced mixture/ignition with increased raw NOX.

[Tim Lamb]

Ok. Thanks.

I don't do much urban driving so I'll hang on to the *cheat* system as long as I can. For a 1600cc engine in a biggish vehicle the performance/fuel consumption is excellent.

[ajh]

I don't know exactly what they did but generally you need heat, pressure and air to create NOx. At low injection levels because the diesel takes in much more air than the fuel needs to burn the temperatures are low so not much NOx forms. At full power the temperature goes up as does the pressure but there is far less excess air as the fuel uses most of it up, so not much NOx forms. The problem occurs when there is just enough fuel injected to raise the temperature and pressure to sufficient levels but there is plenty of excess air present so NOx becomes a problem.

So yes the only control available is how and when you inject fuel.

On a test you can probably avoid this high NOx part of the operating cycle but the power curve would make normal driving difficult.

Adblue is injected into the exhaust to react the NOx back to Nitrogen and steam in a catalytic converter so its use is linked to this part of the fuel-rpm map.

What I cannot understand is why modern diesels with particulate filters and adblue are still being vilified when their levels of pollutants are an order of magnitude lower than a 2010 diesel without those, I still drive a non DPF non Adblue diesel from that era, though only did 1500 miles per year for the past three years.