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'Hybrid power', said Lexus IS Chief Engineer Naoki Kobayashi at the launch of the third generation Lexus IS in 2013, 'is both the personality and the biggest strength of our brand'. Proof of that was delivered with the IS 300h, a car that offered independent-thinking buyers in the compact executive saloon sector in this century's second decade a real alternative to the kind of four cylinder diesel engine that most would otherwise have chosen.
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History
Buying a compact executive saloon from the 21st century's second decade, something like a BMW 3 Series, an Audi A4 or a Mercedes C-Class? Then you're probably buying a diesel. Should you be? Lexus has always thought not. For the same kind of money, their MK3 model IS300h petrol/electric hybrid always offered a quieter, cleaner, more economic and better equipped alternative. Best of all perhaps, it's different.
For some, that'll be reason enough to try it. Most though, will need a bit more convincing. In which case, the efficient returns - quoted in period as a combined cycle 65.7mpg figure and 99g/km of CO2 - should get your attention. If that's piqued your interest, then a glance at the car itself should keep it. So is it a model you should add to your wish list? Let's find out.
The MK3 IS 300h was usefully updated in 2017, but when production finished in 2021, this model line wasn't replaced, Lexus directing customers instead to the slightly larger ES saloon.
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What you get
Lexus switched decisively from bland to bold with this MK3 model IS and the post-2017-era revised version adopted an even more assertive persona. It's difficult to believe that when work first started on this third generation design back in 2008, the original plan was for it to be a badge-engineered Toyota Avensis. Thankfully, common sense prevailed and what we ended up with is a properly credible alternative to the established premium players in this segment. As with the earlier version of this MK3 IS model, the saloon body style was all that Lexus was prepared to offer.
And inside? Well with most rivals in this segment from this period, original buyers had to spend quite a lot to get a really luxurious-feeling cabin but in this IS, there was a premium feel to the interior right across the range. The mid-term facelift update changes made here were as subtle as the outside ones, with perhaps the most significant alteration being a slight reduction in the width of the console provided for the audio and ventilation controls. That allowed the driver and passenger knee pad panels to run right up into the centre stack where twin vents got separated by a lovely analogue clock.
Above that sits the obligatory infotainment screen, this the 7-inch monitor provided with the 'Lexus Media Display' fitted to most IS models. This isn't the touchscreen set-up you'll find in most rivals, but it works quote effectively via a rotary dial near the gearstick that lets you click through the usual audio, telephone, navigation and car-related segments, plus there's a section that adds further climate control features. Go for one of the really plush variants and you may get yourself a version of this car fitted with Lexus's larger 10.3-inch screen, provided as part of the 'Lexus Premium Navigation' system. With this though, you have to have what Lexus calls a 'Remote Touch Interface controller', essentially an eight-way moveable 'mouse' that works a screen cursor requiring quite a subtle touch. Overall, we prefer the functionality of the lesser set-up.
And in the back? Well the lengthened wheelbase of the MK3 IS model always offered much more rear space than the old pre-2013 second generation design could provide, but it's still fairly compact in the rear, though that's also the case with most obvious rivals. There's really only space for two in the back, something guaranteed by the extremely prominent transmission tunnel. As for the boot, well the fact that batteries must be housed beneath the floor of the hybrid IS 300h model robs this trunk area of 30-litres of space. Need more space? Well, unlike rivals, there's no estate body style option but if you've avoided entry-level trim, there is the option of being able to push forward the rear seatbacks.
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What to look for
We really struggled to find too many dis-satisfied Lexus IS owners. Not that we expected to find many. The brand has an enviable reputation for reliability and dealer service and that appears to have been continued here. Of the issues that did occur, most seem to be connected with the 12v battery - or other electrics. Noisy creaking brakes seem occasionally to be an issue. One owner had rear shock absorbers that were weeping, a front parking sensor failure and a noisy whirring sound from the dash.
We did come across a few reports of drivetrain vibrations. On the IS 300h models affected, this apparently sets in between 1,200 and 1,400rpm, so look out for that on your test drive. We did come across a couple of owners who complained that on one occasion, their 300h models wouldn't start. In one of these cases, this was because the car had been left for a few weeks. Finally, in one instance, an owner reported a problem with the auto wipers not working. Otherwise, there's little else to report. Check for alloy wheel scuffs - and insist on a full service record.
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Replacement parts
(approx based on a 2018 IS 300h- Ex Vat) An air filter costs around £16 and an oil filter costs around £7. Brake pads sit in the £30 to £35 bracket for a set. Front brake pads cost in the £23-£33 bracket; it's around £26 for rears. Front brake discs cost in the £37 bracket; it's around £63 for rears. Wiper blades cost in the £4 to £13 bracket. For a replacement wing mirror glass, you're looking at about £28. A thermostat is in the £16-£44 bracket.
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On the road
Unlike the brand's slightly smaller CT 200h hybrid model in this period, the IS 300h was more than a smartened up Toyota Prius, instead based on a proper large Lexus, the BMW 5 Series-sized GS 300h. True, the 2.5-litre engine used may only offer four cylinders but it does develop 178bhp, with a further slug of power contributed by an electric motor, resulting in a combined 220bhp output. That's enough to easily match the performance of the rival 2.0-litre diesel models at which this car was aimed, 0-62mph occupying 8.3s on the way to 124mph. Why just 124? It's down to use of a special geartrain for the electric motor that reduces weight and cuts friction in return for restricted flat-out pace - a reasonable trade off in our book. After all, when was the last time you drove quicker than 120mph?
If you are going to be driving this car hard, then you'll find that the rubber belt-driven CVT 6-speed auto gearbox (installed because the ordinary IS250 model's conventional mechanical unit didn't fit) can start to frustrate attempts at meaningful progress. We've yet to drive a CVT auto from this period that responded to the throttle (and in this case the gearshift paddles) in the way that it should - and here, the same issues remain. Plonk down your right foot and there's a noticeable pause before the transmission adjusts its gearing, after which there's another thrashy gap between the revs rising and the pace increasing.
This is one reason why this IS struggles with its 'sports saloon' billing. The other is the way that the hybrid system goes about creating its impressive efficiency by allowing the engine to rev up and down in a way that's quite unconnected to your actual road speed. As drivers, we tend to rely on these auditory cues to gauge how fast we're going - for example during deceleration when you hear the engine note play down different tones through different gears. In this Lexus though, you can be decelerating while the engine note is ascending the scales. It all takes a bit of getting used to.
Lexus' answer to this problem was rather novel, a little switch that activates a loudspeaker emitting a synthesised 'engine' noise, its pitch governed by the speedometer. Yes really. As you slow, so does the aural accompaniment. Throw in a downshift and you'll hear the sound flare in response. You even get six frequency registers for the six gears you control via the steering-wheel paddles. A gimmick? In almost any other car, we'd have said so but here, it really does help you attune with hybrid motoring that little bit quicker. The noise synthesiser even makes a reasonable attempt at simulating a V6 growl at full throttle - though personally, we'd have tuned it to change up to the sound of the Lexus LFA supercar's howling V10. Maybe that's just us. If you find the whole set-up annoying, you can easily switch it off, but you shouldn't need to for once up at cruising speeds, it doesn't intervene anyway, this IS 300h then reverting to the kind of whisper-quiet progress that was previously the preserve of top-end luxury saloons.
At lower speeds, as with most hybrids, the car can trickle along powered by the 230V nickel metal-hydride battery pack only (as it will from start-off), or with just the engine (if you're giving it full throttle) - or more usually, with a combination of both, something you can monitor via a graphic display in the centre of the dash. And, unlike, say, a Honda hybrid, you don't have to have that combination approach if you don't want it. As long as the engine's warmed up, pressing an 'EV' button near the gearstick will keep the car in all-electric mode from anything between a few hundred metres and just over half a mile, provided that there's charge in the battery and you keep to below 25mph. Once you do need to use the engine, you get the usual hybrid benefit that power which would otherwise be wasted while braking and accelerating can be used to charge the batteries that drive the electric motor. Readying things for the next time you want to trickle along in all-electric silence.
Once the engine has cut in to dominate proceedings, it'll be a case of making the best selection from this standard 'Drive Mode Select' system, a set-up that tweaks engine output, throttle response, gearshift times and even air conditioning functionality through four main settings. There's 'Normal' if you want to leave the software to do its own thing but otherwise, you can select 'Eco' (for efficiency), 'Snow' (for slippery roads) or 'Sport' (for performance motoring that comes with the accompaniment of a red-tinged hue on the instrument panel ahead of you).
Those likely to want to be selecting 'Sport' on a regular basis are the folk being targeted by a firmer-sprung and more dynamically-inclined F Sport variant which also comes with the option of an AVS Adaptive Variable Suspension system that gives you a fifth 'Sport+' option on the Drive Mode Select controller. Thanks to sensors that automatically adjust the suspension performance at all four wheels in response to your driving style and road surface conditions, AVS enables you to adjust the car precisely to suit the mood you're in and the road you're on.
Even without it, we found the handling of this car surprisingly good. Developed at the fearsome Nurburgring Nordschliefe, it tackles the bends really nicely thanks to a bodyshell 10% stiffer than that of the previous generation IS model and a redeveloped double wishbone front and multi-link rear suspension design that decreases body roll by 25%. Unusually for a Lexus, the steering is particularly good, with pin-sharp accuracy and a nicely weighted feel, despite the all-electric set-up.
The ride's good too, even if you choose a car fitted with 18-inch wheels and the F Sport model's firmer suspension, with enough suppleness about it to cope with our hopeless road surfaces. Plus the stability control system is one of the best in the business, intervening gently and almost imperceptibly. Get this car on a test track with all its electronic aids disabled and you'll find a chassis that's as playful and talented as you'd expect for a car that's enjoyed thousands of hours of honing around that infamous bit of tarmac in Germany. As good as anything in the class from this period? We'd say so.
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Overall
Be honest. You weren't originally thinking of buying a car of this kind with a hybrid engine were you? Having second thoughts? If you were, we wouldn't blame you.
Hybrid power, you see, suits the IS perfectly. Buyers tend to be drawn to the Lexus brand for its quality and refinement and the whisper-quiet take-off you get in this car only serves to underscore its feeling of peerless build integrity. At low speeds, you'd almost believe the engineers if they told you this thing was propelled by goose down.
And once properly on the move? Well as we've said, it's certainly true that a good turbo diesel will give you a sportier drive - this car's CVT auto gearbox doesn't help it in this respect - and that diesel might also give you better real world economy. But this Lexus is certainly fast enough and impressively frugal on its cheaper green pump fuel.
It's a car then that, rather refreshingly, flew in the face of established thinking in the BMW 3 Series segment during its production period. Smart, quiet, luxurious and well equipped, it's a model you can feel proud of amongst a sea of German-badged alternatives. Not an obvious choice perhaps - but then that's precisely why you might want one so much. Independent thinkers should form an orderly queue.
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