Audi A4

Can 12 million customers be wrong? By 2015, that's how many people had bought Audi's A4 and its predecessor Audi 80 model over the last four decades.

This mid-sized executive segment contender is the car that's played the biggest part in making the Ingolstadt brand the success story it is, the A4 these days accounting for over a fifth of the company's total output.

All of which means that this fifth generation B9 version had to be very good indeed. Contrary to the impression offered up by its appearance, this was actually one of those rare things, a genuinely new car.

Over 90% of it was completely re-designed, while the rest was fine-tuned and the result in 2015 was a package of far-reaching improvements.

Many of these were made possible by the headline change, the adoption of a lighter, stiffer and cleverer 'MLB Evo' chassis that made the most significant contribution to the massive 120kg weight saving this model enjoyed over its B8 predecessor.

That made this car up to 21% more economical than it was before and Audi promised that it would also make the A4 faster and sharper to drive too. Certainly the A4 needed to improve its dynamic repertoire.

It was (and is) after all, the only remaining volume compact-to-mid-sized executive model without an enthusiast-orientated rear wheel drive set-up, so must provide driving satisfaction in other ways.

The freshly-developed five-link front and rear suspension set-up ought to help here, with its optional adaptive damping.

So will the rejuvenated engine range which offers revolutionary combustion technology to TFSI petrol buyers.

Plus there's plenty of hi-tech cleverness fitted to plusher models; quattro 4WD, sophisticated Matrix headlamps that think for themselves and an Adaptive Cruise Control system that at low speeds will even drive the car for you.

Add in segment-leading connectivity and, as ever, the classiest cabin in the sector and you've potentially a very strong proposition indeed.

In its original form, the B9-series A4 sold until mid-2019, when it was substantially updated.

It's the pre-facelift B9 models we're going to check out for used buyers here.

Audi believes firmly in evolution rather than revolution and if proof of that were needed, then this fifth generation B9-series A4 provides it.

The lines are sharper than those of the old B8, the stance lower and the shape a little bolder but the changes are all very subtle, in line with the need to protect the values of previous models.

As ever, there's the option of an Avant estate bodystyle as an alternative to the saloon and both variants seized the opportunity offered by this MK5 model's new MLB Evo platform to offer buyers a slightly larger car than before. As ever though with an Audi, it's the interior that'll really sell you this car.

The Ingolstadt brand isn't as far ahead of its rivals as it used to be in this regard but this remains the defining cabin in its class from this period, with surprising headroom, a wraparound design and a premium feeling of space and safety.

The optional 'Virtual Cockpit' that many original buyers chose replaces the entire instrument binnacle with a 12.3-inch LCD colour monitor and has a layout that's fully digital and customisable, with smart 3D graphics and highly detailed effects.

Anything this set-up can't tell you will almost certainly be covered by the slimline MMI infotainment display that dominates the top of the dashboard.

It's 7-inches in size on standard models - or 8.3-inches if you get a car whose original owner opted for the top 'MMI Navigation Plus with MMI touch' system, with its crisp 3D maps and responsive Nvidia graphics.

In the rear, you ought to notice the benefit of the extra 12mm of wheelbase length this fifth generation model enjoys over its predecessor.

Audi says there's 23mm more legroom in the back than there was before but to be frank, it doesn't feel that much bigger.

And out back? Well despite this MK5 A4 model's longer length, boot space is identical to that provided before.

That means you get the same 480-litre capacity also provided by BMW 3 Series and Mercedes C-Class rivals.

If you need more, there's the versatility of a 40:20:40 split-folding rear backrest, the centre part of which is very useful if you need to carry longer items like skis.

Please contact us for an exact up-to-date valuation.

Most owners in our survey seemed happy.

The most reported faults related to interior trim and non-engine electricals.

Look out for bodywork scrapes and kerb damage to the large alloys.

We've had some reports of issues with wear to the side bolsters of the leather seats, as well as squeaking front brake pads, so it's worth looking out for both of those.

There were a few issues with the car's infotainment system, with phones not connecting properly and flickering screens being the main problem.

Rattling parcel shelves and buzzing interior trims were also reported.

The DSG automatic gearbox should be checked to make sure it's had a regular oil and filter change, as should the quattro four-wheel-drive system. Many A4s will have been company or lease cars and, as a result, you should check the condition of the bodywork carefully.

The high-quality fit and finish of an A4 also makes it an ideal candidate for clocking, so ensure the history is absolutely verified.

There were three manufacturer recalls on the A4, all for models built before December 2016.

One concerns a potential seat backrest fault, one was for seatbelt pre-tensioners and airbags and a third affected TFSI engine coolant pumps.

(approx based on an A4 2015 2.0 TDI 150PS - Ex Vat) An air filter costs in the £44 bracket.

An oil filter costs around £13.

A fuel filter is around £37.

Front brake pads sit in the £90 to £130 bracket for a set; for a rear set, it's around £57.

Front brake discs sit in the £77 bracket; for a rear pair, you're looking at around £110.

A thermostat costs around £105 and a water pump is around £108.

In a segment dominated by rear-wheel drive rivals, Audi continued to offer this B9-series A4 with a choice of front or four wheel drive layouts.

That's a key reason why the brand had to engineer this car very cleverly to get close to the kind of driving satisfaction offered by competitors.

In this, the engineers were helped this time round by this MK5 model's adoption of a hi-tech MLB Evo chassis that played a key part in enabling this car to shed up to 120kgs of weight.

This platform also gave Audi the opportunity to develop a sophisticated fully-independent five-link front and rear suspension arrangement that delivers superb standards of ride.

Ultimately, what all this creates is a more comfort-orientated mid-sized executive contender, but it's still one that can be hurried quite quickly through the bends thanks to very little body roll and superb traction.

Most models offer the option of either a six-speed manual gearbox or this car's seven-speed S tronic auto transmission, while under the bonnet, the majority of buyers will choose the 2.0 TDI diesel engine.

This is a variant that in 150PS form can return 99g/km of CO2 and nearly 75mpg on the combined cycle.

In pokier 190PS 2.0 TDI guise, there's the option of quattro 4WD.

Quattro is also on offer to buyers of the six cylinder 3.0 TDI version of this car, who get to choose between 218 and 272PS outputs.

Petrol people meanwhile, get a TFSI range offering an entry-level 150PS 1.4-litre unit and a sophisticated super-efficient 2.0-litre powerplant developing either 190 or 252PS.

The quicker version comes with quattro, as do high performance S4 and RS4 models that use a potent 3.0 TFSI unit.

Here's a car created by a brand that knows its customers.

The magazines might tell Audi to bring us futuristic looks and an uncompromisingly dynamic drive but Ingolstadt knows that buyers in this segment really value comfort, class and quality.

All three attributes are prioritised in this lighter, more agile and more advanced fifth generation A4. Even more than before, this A4 feels like a car that's been lovingly and very carefully considered.

The depth of engineering and the thought that's gone into the tiniest details combine to further enhance the warm fuzzy feeling that's charmed Audi customers for years.

If you're one of those people, then you'll like this car very much.

And even if you're not, you'll find it hard not to be impressed by way it systematically ticks almost every box on the compact executive market wish list.

It's very thorough.

Very elegant.

And very Audi.