The Kia Sportage 1.7 CRDi took backseat to its petrol counterpart, the 1.6 GDi, at Fleet News recently giving us the chance to compare the two.

The 1.7 CRDi is achieving around 44.4mpg, as opposed to a claimed combined of 54.3mpg, while the 1.6 GDi returned 33.1mpg, less than its claimed combined of 44.1mpg.

Not good if you’re a high mileage driver, even when you take into account the price differential between fuels and employee’s BiK charges.

The problem is that, while the 1.7 CRDi engine is very responsive, the 1.6 GDi is sluggish and requires you to rev the engine at a much higher rate to get any sort of performance. Admittedly it’s difficult when comparing the slightly bigger diesel engine, but the performance of the petrol version was extremely disappointing.

The P11D value of the 1.6 GDi is £17,110 compared to £20,425 for the 1.7 CRDi, while CO2 emissions for the petrol version are 149g/km as opposed to 135g/km for the diesel.

Given the 3% diesel BiK surcharge, an employee driving the diesel variant would fall into a 20% BiK tax band, compared to 19% for the petrol car.

That would mean a 20% taxpayer driving the 1.6 GDi paying £650 per year compared to £817 for an employee driving the 1.7 CRDi.

But how do the employer’s costs compare? First year VED rate for the 1.6 GDi is £130 compared to £115 for the 1.7 CRDi, while Class 1A NIC costs are £449 and £564 respectively.

Meanwhile, the all-important running costs on a three-year/60,000-mile cycle favour the petrol variant on paper.

Its 37.07p per mile rate includes fuel at 13.72p per mile, compared to 38.18p per mile with fuel at 11.64p per mile for the diesel.

However, if you travel 100 miles in the 1.7 CRDi at 44.4mpg you will pay around 14.38p per mile for the diesel, compared to 18.75p per mile at 33.1mpg for the petrol.

It all goes to show that when it comes to the Sportage, don’t be swayed by a cheaper P11D and running costs that don’t reflect the real world.