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Hi Naseem,

If you’re driving the M50 a lot, it probably  depends what time of day… Post-10am or pre-4pm and you’d probably get up enough speed to be able to keep the DPF clear and so it wouldn’t be a problem, even with the relatively low mileage. If you’re stop-start driving and not getting into a proper heat cycle, then no, go for petrol instead. Ford has that brilliant little 1.0-litre EcoBoost turbo petrol engine.

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Hi Gerry,

Of the two, I’d prefer the 1.3 diesel. Neither is an especially refined engine by modern standards, but the 1.7 is a terrible old thing – incredibly noisy, rattly and prone to stalling when driving in stop-start traffic. The 1.3, if you get it with the 90hp output, has decent performance, is very economical and doesn’t seem to give too much bother. Great that you’re doing your own servicing, but beware of what effect that may have on the resale value as most buyers prefer to see a healthy book of dealer service stamps.

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Hi Max,

Well, the official combined fuel economy figure is 51.4mpg, but that sounds a bit optimistic to us. Doing short journeys shouldn’t be a major issue as it’s a petrol engine, but a bit of gentle driving should get you at least past the 40mpg mark, unless you’re stuck in stop-start traffic all the time. I wouldn’t bother using premium petrol, as you’re just wasting your money. The engine is designed to work on standard 95RON pump fuel, so just use that, but make sure you buy from a reputable supplier.

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Hi Declan,

It’s a tough one. Generally I’d say for the moment, diesel is still best for that kind of mileage, especially day-to-day. A model with a good stop-start system should help keep the consumption down in heavy traffic (Mazda’s system on the 6 2.2 diesel is especially good) and those long motorway miles are just what diesel was designed for. A plugin hybrid is really for those doing short urban journeys most days, with only an occasional long trip, so I don’t think any would be really suitable for you. It would be worth looking at a new-shape Toyota Prius hybrid though – we managed to average 60mpg in one recently over the course of a week, including several long motorway runs, so it’s worth thinking about.

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Hi John,

No, it’s not just another cost to the consumer. Stop-start systems are designed to prevent the car from running the engine unnecessarily at standstill when doing so would be at its most wasteful of fuel. After all, if you’re not moving then what is the point in having the engine on? Stop-start systems are specially designed with either a beefed-up alternator or an integrated starter/generator so that it can handle multiple stops and restarts in rapid succession, and it’s estimated that on an average car, stop-start can save as much as ten per cent of overall fuel consumption – not to be sniffed at, never mind the benefits to city-centre air quality.

Admittedly, the car makers have brought in stop-start to bring their cars' official CO₂ and fuel consumption figures down, and the benefits are only really felt if you are stopping and starting regularly. If you spend all your driving time on the motorway then you won't use the system at all.

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Hi there,

Right, I'll be honest - we had to get on to Nissan Ireland for help with this, but it came through in spades.

Over and above the SV model, the SVE added Xenon headlights, Intelligent Key, illuminated passenger sunvisor, seven-speaker BOSE audio system, 17-inch alloys and rear parking sensors.

The engine has a timing chain, not a belt, so it doesn't need replacement,  but it does need to be inspected at regular intervals. Any Qashqai with a full service history should be fine on that score.

In terms of economy, the 1.6 petrol Qashqai got 44mpg overall while the 1.6 diesel got 55mpg, or 60mpg if it was fitted with the stop-start system.

Hope that all helps

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Hi Barry,

It depends on whether it's the 90hp versions (with CO₂ emissions of 109g/km) or the 134hp stop-start version (CO₂ of 94g/km). It'll be either 15 or 16 per cent of the open market selling price, which is around the €16,000 mark - so around €2,400 to €2,500. 

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Hi Elizabeth,

Ok, there's a simple answer and a not-so-simple answer. The simple answer is that the Fiesta is more economical. Going by the official figures, you'll get 78mpg on the combined cycle from the Fiesta (and that's for a model without the stop-start system fitted) and 57mpg from the Audi (that's the 125hp engine with a manual gearbox and 16-inch wheels).

Now, the not-so-simple bit. It depends on how and where you drive. If you drive mostly short journeys and mostly in town, then the diesel is not going to give its best, and that 78mpg figure is pure fiction anyway. I'd say in daily driving you'll probably get closer to 55mpg. The Audi, if driven with a bit of care and attention, should easily get 40mpg, even around town. So there's a gap, but it's not so big as you'd think.

The reverse is true if you're doing lots of long journeys at a steady motorway cruise. The Fiesta would come into its own and you''d probably squeeze 60mpg, maybe 65mpg from it. The Audi probably wouldn't get much above 45mpg, maybe a bit less, doing such journeys.

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Hi Stephen,

I agree it can be a little annoying on an automatic car, as you can't decide when you do and don't want it to happen at any given moment. I'm sure you're aware that there is a button on the dashboard to disable it at any time, but it sounds like you'd rather disable it completely. Sadly, there's no legitimate way to do this. The car's official CO₂ emissions and fuel economy figures rely on this feature, so even if you find a fuse or relay to remove for the system there will at the very least be a warning light on in the dashboard - and it may even go into 'limp home' mode.

By way of explanation, the 'combined cycle' is a relatively low-speed and short duration (standardised) test cycle all the car makers adhere to for their CO₂ and fuel consumption figures. Stop-start makes a big difference for this as the car is idle for considerable amounts of time. In the real world, this tends to happen only in slow traffic or in town with lots of traffic lights. You would see a saving in those situations, but in reality it'll be small.

Sorry not to be of more assistance.

Expert answer

Hi George,

We'd need to reg. number to give you a definitive answer, as the official emissions rating for that car depends on a number of factors, including the factory-fitted wheel size, whether it has stop-start and whether it's the five- or seven-speed automatic gearbox. Possibilities include:

- 16-inch wheels, five-speed auto, no stop-start: 154g/km - Band C - €390 per year

- 16-inch wheels, seven-speed auto, stop-start: 129g/km - Band B1 - €270 per year

- 18/19-inch wheels, seven-speed auto, stop-start: 138g/km - Band B2 - €280 per year

Come back to us with either the registration or all those details and we'll give you the definitive answer.