How clean are new diesel cars?

[Quacker]

Originally Posted by elotro

I never said it was 4 times on the XC60.

When I bought my car, I checked Volvo S90, Audi A6, Volkswagen Arteon and BMW 4 series. I also checked a couple more just out of curiosity and I remember the figures I got were around those 2-4 times. I think on the XC40 there was a big difference but there were only a T5 and a D4, that might be the one.

I know they are all bad, and they will be banned exactly at the same point, but if one type of engine is worse than the other, it is worse, there is no point in trying to cover that up. Those are the figures.

Figures are no good unless they are put in context, even when they are relative.

[Haldex]

Originally Posted by jonnyu

https://www.volvocars.com/uk/own/mai...tenance/adblue

The AdBlue should reduce the Nox emissions according to Volvo:

Yes, that's what it's there for.. In non-AdBlue cars this is done by EGR (https://www.cambustion.com/products/egr). All things equal- normally AdBlue and EGR versions of the same vehicle have same NOx emissions - you can lookup the numbers in the above UK gov website.. AdBlue cars normally have slightly lower consumption though- but this is (financially..) compensated by AdBlue consumption.

Originally Posted by elotro

if one type of engine is worse than the other, it is worse, there is no point in trying to cover that up

Define "worse"?.. We all know that since the antidiesel hysteria started - diesel sales went down drastically- yet the pollution figures went up..

[jonnyu]

Originally Posted by elotro

I never said it was 4 times on the XC60.
Those are the figures.

The question you should be asking is what type of mechanism are these brands using to cheat on the emissions now. When you see this disparity of values, something does not add up.

[Haldex]

[Begonia]

During the week I often do quite a number of short runs in my XC90 Inscription. This is not an excellent position to be in, I know, and perhaps I should have initially purchased a petrol engine, not a D5 diesel.

Very occasionally, when I get home I switch off the engine and the car does an over-run. It's a strange experience to witness and one wonders why it is doing it.

Today it did it once again and so I rang the dealership.

The Service Manager explained that, on a good run, the engine would heat up to a high enough temperature for the particulates to burn off naturally.

With short runs the engine does not get hot enough to burn off the particulates and so the 'software technicals' are set up to allow the engine to go into over-run and raise the engine temperature to 600 degrees C so as to do this 'burn off' as a separate process.

(Not a lot of people know this, I suppose, but you and I know it now. )