VW. Some news at last!

[The Natural Philosopher]

They will be slower and less economical.

[The Natural Philosopher]

Yes, we do know that. If there wasn't some performance hit from meeting the regulations without cheating, they wouldn't have cheated would they?

[Dave Plowman (News)]

But what they don't say is what effect the 'fix' will have on performance and economy, etc.

[Chris Bartram]

but increasing EGR to reduce the NOx increases particulates due to incomplete combustion. As Adrian pointed out, the DPF will catch that, but it will need more frequent regen.

[F]

They just said 'may need new injectors and catalytic converter'...

[Michael Chare]

It does make you wonder how many people will bother to get their cars changed. Could be a big saving to VW.

[Dave Plowman (News)]

In the US, it could be they have no option. Since the reason for the tests there is to control emissions. So if they don't accept the mods could be prosecuted.

[tim.....]

That's almost certainly a peak amount bandied around by the vested interests for effect

the running average could be as little as 1.5 times the allowed

tim

[tim.....]

That's hardly surprising when they contain such nuggets as:

"wash your car after every rainfall"

I kid you not

tim

[tim.....]

I doubt that you could claim any compensation for failure to meet the "book" NO2 value

you could if they forced you to have a modification to meet that requirement and that resulted in a serious loss of performance.

tim

[tim.....]

I doubt anyone knows - Yet!

tim

[tim.....]

why

if they are made more "emissions efficient" logic sys that will be because they burn the fuel more efficiently and thus get a better miles per gallon

This bit I agree with

tim

[Tim+]

tim.....

As I understand it, burning fuel efficiently usually means at higher temperature. The higher the temperature, the higher the NOX.

To reduce NOX, combustion temperatures need to be reduced, with an associated loss of efficiency.

Tim

[Andy Burns]

AIUI the VW TDIs can already do multiple injections per stroke.

[Andy Burns]

Perhaps.

WGAF what it does on the road, compared to what it does on a (non cheated) test, if there's a big difference it's the test's fault.

[dennis]

Everybody knows that mpg, etc. vary with driver, BUT, the emissions of NOX are a limit which they should not exceed whatever the driver does.

[dennis]

How much zeolite would you need to reduce the N2 levels to give a significant reduction of NOX?

[dennis]

They won't poison as many asthma suffers.

[Hanny Z]

No perhaps about that.

We're discussing the discrepancy between the real world and the cheat test.

[F]

And now they've told the US that some (read in the 100s of 1000s) can't be fixed with software and will need a second tank for urea and a replacement cat.