LEXUS and Toyota have garnered plenty of plaudits for their industry-leading hybrid cars, and rightly so.

They may not be perfect, but they’re a long way ahead of anything anyone else has managed. They have stuck their heads above the parapet and are rightly reaping the rewards.

Toyota is about to become the world’s biggest car company, so it’s odd then, that with a comparatively simple thing like the diesel engine – essential to the European market – Toyota has never really aced it. The diesels in cars like the Avensis have always been distinctly average.

And the first diesel in a Lexus isn’t much cop either, I’m afraid. And the least edifying part of it is when you come to a stop.

Numerous times on each journey, there comes that moment where you have to put the car back into first gear. It’s not the most rewardingly tactile experience in the IS.

In fact, on some occasions forcing the gearstick back up through the gate feels like breaking a leg off a roast chicken. There’s resistance, then a slight snap and pop and then you’re back in first.

It’s not a feeling that inspires much confidence, especially if you’ve caressed an Audi or BMW box about, and suggests that Lexus hasn’t got its powertrain quite right. Even more evidence of that are the myriad vibrations coming from the engine bay.

Depending on where you hold the accelerator, you can produce deep rumbles or high fizzing, and plenty in between. Under acceleration, the cacaphonous symphony gets to perform its various pieces. And because the first couple of gears are so short, you are treated to this performance on a regular basis.

Fortunately, once you have trudged your way through all six gears up into cruise mode, the IS is pretty quiet and refined – the calm after the storm.

The problem with the Sport is that shorter gearing over the standard versions has made an already not very frugal diesel even thirstier.

Achieving 35mpg has proved beyond my powers, with 32mpg a more typical figure. I desperately want to like this car. It looks fantastic and it’s got lots of kit as standard. But I’d find it a hard car to love over three years of driving.

Price: £26,968 (as tested £30,278)
Mileage: 6,803
CO2 emissions (g/km): 195
Company car tax bill (2007) 40% tax-payer: £232 per month
Combined mpg: 38.2
Test mpg: 32.2
CAP Monitor RV: £12,175/44%
Contract hire rate : £511
Expenditure to date: Nil
Figures based on three years/60,000 miles