HERE’S A PIECE of throwaway trivia: Lexus’s previous-generation IS200 put out 231g/km of carbon dioxide - about the same as the Honda S2000 or the Jaguar X-type 2.5 V6. And, incidentally, precisely the same amount as the new, larger-engined IS250. That CO2 figure battered UK sales of the IS200, a car whose sonorous six-cylinder motor we otherwise really enjoyed. As did buyers, for a while: the IS200 posted more than 7000 British sales per annum at its peak, which had fallen to around 3000 a year once carbon dioxide emissions started costing company car drivers serious money. And that meant that when the new IS arrived in Europe, there had to be a diesel version. So here it is: Lexus’s first diesel, the IS220d, on sale in January, costing from £22,200, (about a grand cheaper than the BMW 320d). Carbon dioxide emissions? A far healthier 168g/km, with economy of 44.8mpg on the combined cycle. The engine itself is a 2.2-litre unit with 175bhp and a hefty 295lb ft of torque. If you’re a diesel fetishist, you might recognise those figures – they’re the same as the Toyota Corolla Verso 180’s, with which the IS shares its engine. It’ll arrive in the Avensis next spring, too. In the new IS, though, it’s quieter than in the Verso. Diesel clatter is muted at idle and, although you’re always aware that you’re at the wheel of an oil-burner, the noise is never intrusive: it’s all but inaudible on part throttle at cruising speeds. It is, though, on the lethargic side until you approach 2000rpm, but then there’s decent enough pull, though not entirely linear, to the high side of 4000rpm, beyond which an orange ring on the dial is lit, turning red at 4500 to warn of the impending rev limit. You won’t often see red: between 2500 and 4000 is where this engine’s best work is done. But even when worked, it seldom feels like it’s delivering the full quota of 175bhp – mostly because of some slight turbo lag. That’s not to say that the IS220d feels slow, it’s just not quite as responsive as we’d have expected. Toyota’s claims of 0-62mph in 8.9sec and a top speed of 134mph, extremely close to the BMW 320d’s 8.7sec and 135mph, don’t feel unrealistic, but the BMW, which is supposed to be 12bhp shy of the IS, feels faster throughout more of its rev-range. Dynamically, the IS220d doesn’t quite match the 320d either. Where it does seem to have an advantage, albeit on the largely well-surfaced Italian roads we tried the car, is in its noise levels, which are very low save for a bit of wind noise from the absolutely enormous door mirrors, seemingly picked from the Land Cruiser production line The IS’s ride is largely good, too, although the odd thump does enter the cabin at low speeds over broken asphalt. At a high-speed cruise the ride is very good, and straight-line stability is also excellent. On the twisty stuff, the IS220 turns out to be agile and competent, but not outright entertaining. It turns in well, displays reasonable body control and has good grip levels, particularly at the front. Once the car’s grip has been exceeded, things are kept under control by a new stability programme which is far more forgiving and subtle than the old car’s, but the IS is not an enjoyable car to drive hard. Better steering would help: although around town the electrically assisted set-up is respectably light, accurate and direct, more feel at higher speeds would really be beneficial. The new IS’s cabin is comfortable, but not quite as successful stylistically as its predecessor’s. Gone are the chronograph-style dials and natty instrument pod, replaced by far more conventional dials, albeit clear ones with a classy finish. No more is there a chromed gearknob on the smooth-acting, short-throw six-speed manual gearbox, either. So there’s less to enthrall you inside, and less flair, which is a shame. At least cabin materials have now been brought up to scratch, though: away from the centre console’s buttons, nearly all cabin plastics are soft-feel, and quality of assembly is first-rate. Cabin accommodation is competitive, too. Front seat occupants get plenty of room, with a widely adjustable steering column and therefore driving position. The seats are pretty good too, though could use a little more lateral support. Rear passengers get fine headroom, but legroom isn’t up to 3-series standards and the transmission tunnel impinges on centre-seat foot-space. Outside, the IS remains a decent-looking car, the long bonnet and high, rising waistline giving it a hint of dynamism. Of course, these things are subjective, but if the 3-series has received stick for its clumsy, contrived details, then it is bettered by its peer here. For plenty of owners, that, the pricing and the comfort will put the IS ahead of the 320d, but while we think the Lexus is a good car, it’s not a class leader. Matt Prior

Our Verdict

The Lexus IS is a sleek junior exec that makes for an interesting alternative but lacks a decent diesel option

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