Why don’t your reviews include information on NOx emissions?

A reader is concerned about the NOx emissions of diesel cars and asks why we don't include this information in our new car reviews...

Used Seat Ateca

I was interested to read your recent comparison of a used Seat Ateca with a used Nissan Qashqai. At the end of the test, you gave various facts and figures about each car, including CO2 emissions, but you didn't give the NOx emission figures. 

Surely when lots of people are concerned about NOx, you ought to give those figures as well? When I next buy a car, I'll be concerned about the CO2 emissions, but perhaps rather more concerned about the NOx emissions.

Nigel Glennie

What Car? says…

We appreciate your concern about these harmful emissions, but we don't include them because they are very low in the latest Euro 6-compliant diesel engines. In fact, Euro 6 diesels have 67% lower NOx emissions than Euro 5-compliant cars.

Both the Ateca 1.6 diesel and Qashqai 1.5 diesel in our twin test have NOx emissions of 52mg/km, which is well below the Euro 6 threshold of 80mg/km.

Used Nissan Qashqai

Unlike older diesels, Euro 6 cars – which are mostly those sold from September 2015 on – use two forms of technology to reduce the amount of particulates coming out of the exhaust system: selective catalytic reduction and exhaust gas recirculation. 

The first measure uses a fluid, commonly AdBlue, to break down NOx in exhaust gasses into harmless elements before they're expelled from the car. Both diesel-engined Ateca and Qashqai models have AdBlue systems. They have small tanks containing the fluid that will need to be topped up periodically via a small filler cap located next to the fuel filler. 

Best family SUVs and the ones to avoid

Buying a car that will transport and protect your family is one of life’s most important decisions. That's why we've gathered together our favourite family SUVs that cater for the growing number of people looking for a mix of space, practicality and sensible running costs, but also a raised ride height and off-road looks.

Practicality is paramount, but that shouldn’t come at the expense of a decent drive. We’re looking for tidy handling, smooth engines and a ride that is comfy enough to ensure the kids aren’t left feeling queasy.

And along with good space inside, we’d like to see a high-quality interior and an infotainment system that’s easy to use and packed with the latest features.

10. Toyota C-HR

The C-HR sits below the RAV4 in Toyota's SUV line-up. Even the cheapest Icon trim comes with a decent amount of kit, and there's also a hybrid version that will help keep running costs down.

Decent to drive and generously equipped, the C-HR makes a good case for itself, especially if you're a company car driver and opt for the hybrid version. However, it's pricer to buy than rivals and doesn't have much space for rear-seat passengers.

Welcome to a French take on the hugely popular Nissan Qashqai – the equally intriguingly named Renault Kadjar. The Kadjar is also a rival to the Kia Sportage, Seat Ateca and Skoda Yeti, but it's the aforementioned Nissan that it has most in common with, because it uses the same underpinnings and engines.

The Renault Kadjar undercuts many of its rivals on costs and CO2 emissions. It's an outstanding option if you’re after a spacious family SUV.

Read our full Renault Kadjar review, see our latest deals or see our leasing offers

8. Audi Q3

The second-generation Audi Q3 offers a stunning interior, complete with Audi's latest MMI infotainment system. It also has plenty of space for both passengers and luggage. All in, it's a very compelling proposition, even if its ride can sometimes be a little firm and some of its engines can sound rough.

Read our full Audi Q3 review, see our latest deals or see our leasing offers

Next: more of our favourite family SUVs >

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