With the BS-VI emissions regulations set to roll in next year, many manufacturers are set to part ways with their smaller-capacity diesel engines. Maruti, though, has chosen to buck the trend and has débuted its new BS-VI-ready 1.5 diesel engine in the Ciaz.

Suzuki’s survival depends on the high-stakes Indian market, where it cannot afford to leave any of its core segments vacant. With diesel cars accounting for around 30% of all Maruti Suzuki sales, and the trusty 1.3 diesel set to see its demise post BS-VI — and demand expected to remain substantial for diesel — the company has taken no chances with not having a diesel model in its portfolio.

I must admit, I was pretty sceptical about Suzuki’s latest diesel effort, given the company’s track record first time round. The Celerio diesel flopped because it was noisy, underpowered and anything but a joy to drive. But the moment I fired up the 1.5 diesel, any misgivings I had quickly disappeared. In fact, I was utterly blown away with how refined this motor is; partly because of my low expectations and also because there is no doubt that this all-new diesel is right up there with the best in class, in terms of NVH. It’s impressively quiet at idle, and when you rev it, you do know it’s a diesel, but noise levels increase in a subdued sort of way. There’s none of that annoying diesel clatter of the 1.3 Multijet or the gruffness of the VW 1.5 diesels, and, quite honestly, I would rate this engine on par with the Verna’s 1.6 diesel, when it comes to refinement. In fact, when cruising, the engine sound is so low that it’s drowned out by road noise, which ironically exposes the Ciaz’s lack of underbody insulation.

The motor currently meets BS-IV standards, but can be easily upgraded to BS-VI norms once the fuel is ready. On paper, this engine is the least powerful in its segment, developing a rather modest 95hp. However, it makes up with a healthy torque output of 225Nm — not quite the class-best figure but, given the fact that, at 1,125kg, the new diesel Ciaz is the lightest car in its segment (a good 20kg lighter than even its Fiat-powered predecessor), it’s good enough to give this sedan sufficient oomph.

First impressions are that performance is more than adequate and power delivery is far more progressive than the peaky 1.3 Multijet. In fact, you do miss the punchy mid-range, which is more linear in the new engine. The shocker is the strong top end and how free-revving this engine is. When most other 1.5 diesels are running out of breath around 4,000rpm, this diesel gets a second wind and comfortably sails past 5,000rpm. It can rev on to a very un-diesel-like 5,200rpm, though power tails off rapidly at this point. What’s genuinely impressive is the smoothness throughout the rev range.

Sadly, the enthusiastic top end isn’t complemented by a strong bottom end. Though turbo lag isn’t as pronounced as in the Multijet-powered Ciaz, the new engine feels quite sluggish at low revs. It’s all but dead below 1,500rpm and you need to cross 2,000rpm for the engine to start waking up. A big reason for the rather tepid low-end grunt is the relatively high gearing. The ratios of the 6-speed gearbox are too spread out, and the gap between the second and third gear ratios is particularly wide. As a result, third gear is extremely tall and that blunts pulling power. Shorter overall gearing would have made the Ciaz more responsive at low speeds, but it may have come at the cost of fuel efficiency, something Maruti would be loath to sacrifice. Not surprisingly, the 1.5 diesel has the best-in-class fuel-efficiency figure (under standard conditions) of 26.82kpl.

One small thing I did notice is that the engine has mild flat spots in its power delivery, somewhere low down in the rev range, which suggests that engine calibration for this brand-new powertrain is still a work in progress.

The car’s 6-speed gearbox comes from the Suzuki parts bin, but is all-new for India. There’s no doubt that future Maruti models using the 1.5 diesel will also get this transmission. It’s slick to use, fairly accurate to slot and is complemented by a clutch that is light and progressive. Like with the engine, Maruti is no longer dependent on Fiat for the gearbox either, which will now be manufactured in-house.

Apart from the new engine, there are no changes to the Ciaz, which means you get the same spacious and airy cabin, a decently long equipment list and a plush ride. The steering has no feel to speak of, especially around the straight-ahead position and reminds you that the Ciaz is not a car for enthusiasts. But then few diesels are.

Maruti has pulled a rabbit out of the hat with the new 1.5 diesel Ciaz, and it has turned out to be far better than expected, considering Suzuki’s lack of experience with diesel technology. Priced at ₹9.97 lakh (ex-showroom, Delhi) for the starting Delta variant, the 1.5 diesel is just ₹17,000 more than the 1.3 Multijet variant, which eventually will be phased out.

The new engine is remarkably refined, has sufficient punch and lives up to Maruti’s tradition of offering the best-in-class fuel efficiency. The 1.5 diesel Ciaz feels more polished and takes the fight to the doorstep of its arch-rival — the Honda City. More importantly, the new 1.5 diesel comes at a time when several rival mid-size sedans won’t have a diesel option next year. Maybe Maruti’s timing wasn’t so bad after all.