Sometimes, and for no immediately apparent reason, I’ll drive a car that adds up to considerably more than the sum of its rather modest parts. Now and again a car comes together in such happy harmony that it leaves you with the impression that it’s rather better than its makers intended.

Such a car is the Audi S3. I’ll remember my hours behind its wheel for the rest of my life, not because it was super-fast or did things other cars can’t do, but simply because it just felt beautifully, naturally, almost ineffably right.

Sadly for me, that drive took place more than seven years ago in the original S3. My time in its replacement was rather less edifying. On sale in Britain in the new year with prices starting at £26,995, it shows that Audi, while seeming to know all there is about how to make a car look right, still has something to learn about how to make them go properly too.

The clean and purposeful shape of the A3 hatch has been subtly yet powerfully improved by a big chin spoiler, gorgeous 18in alloy wheels, a small roof spoiler and a rear valence. Inside, the already class-leading A3 interior has been enhanced by an aluminium-effect finish to the pedals, gearlever and air vents. So far, so good.

Problems start to mount when you look beneath this veneer of sophistication. When choosing which engine should power the S3

I just presumed they’d use the 3.2 litre V6 in the A3 as that already produced 250bhp before they started tinkering with it. Not so. In fact they plumped for a 2 litre four-cylinder motor that derives its 265bhp from being turbocharged to within an inch of its life.

What this means is that while the S3 goes like hell — 0-62mph in 5.7sec — the quality of that performance is nothing like as endearing. The car suffers from turbo lag, which often means there is a considerable pause between your right foot requesting a gob of power to squirt past a long lorry and it actually arriving. In that time a less powerful but normally aspirated car such as the A3 3.2 quattro would already be on its way.

And while the V6 A3 howls sweet six-cylinder music, the highly stressed four-cylinder motor in the S3 sounds anodyne at low revs and increasingly harsh as the needle sweeps around the dial. I wonder how many people will think it worth paying the extra £760 that the S3 costs over the A3 3.2 quattro when its less responsive and refined engine gives a mere 15bhp extra.

To be fair, Audi has stiffened the springs and dampers to give the S3 a more sporting ride, but even this has not been entirely successful. The car feels uncommonly well planted on the road and, combined with its quattro all-wheel-drive system, it hustles its way down the lanes with great security and authority. But fun? Not from where I was sitting.

And while the ride quality was hard to fault on the glass-smooth German autobahns, it crashed and banged about enough in the towns to make me suspect it is not going to be an ideally comfortable companion on a British B-road.

Indeed, I concluded that the best way to handle the car was to ease off the gas and drive as quickly as possible without making any great effort. And I suspect that is how most S3 drivers will go about their business when the road is open and clear. Without having to put every ounce of concentration into your driving, you can savour the ergonomic effectiveness, luxurious quality and, yes, raw beauty of the cabin and you may figure this is just one good reason why you should have it ahead of any other car in the class.

To an extent you’d have a point. Most Audis have a set of red-hot competitors, but not this one. Outside its own group, only the BMW 130i and the Mercedes Sports Coupé C 350 can be thought of as true rivals, neither of which is a fine example of its creator’s work. But I’d rather have a VW Golf R32 than any of them: it has the same basic chassis as the S3 but with a better blend of ride and handling, the aforementioned 250bhp V6 motor and is £2,755 cheaper.

I spent last weekend in one and thought it a fine and underrated car — words that, a long time ago, I once used to describe an Audi S3. Time flies but, it seems, not always in the right direction.

THE OPPOSITION

Model Volkswagen Golf R32 £24,240
For Sweet V6 engine can be both fun and refined
Against Quite thirsty if you push it, needs a bit more punch

Model BMW 130i SE £24,770
For Strong engine offers good performance and economy
Against Price, looks, not much fun to drive