Nowadays diesel and turbo gasoline powered engines are equally strong, but just in the middle class, the compression ignition engines are still more popular. But sometimes, the gasoline engine is the better alternative. So, does diesel still make sense? Auto motor und sport gives us the verdict by pitching the Mercedes C 250 against the C 250 d, both in T-Modell guise.
Gasoline? Uninteresting. This is what most customers looking at middle class models think when facing the task of deciding which engine variant of the new Mercedes C-Class or VW Passat is the best – a remnant of the past, when petrol engines looked dated in comparison to the powerful and economical turbo diesels. But since the prevalence of modern turbocharged gasoline engines, a lot has changed in the middle class.
In Mercedes’ case, the new petrol engines can successfully compete in any disciplines with the diesels, becoming a really sensible alternative to the ”d” labeled variants.
Mercedes C 250 against C 250 d
Perhaps you need to take this small arithmetic exercise into consideration before reading ahead: 50 times, this is how many times you could fill up the C 250 with gasoline at today’s fuel prices before the additional (initial) cost of the almost equal in strength C 250 d fades away. Of course, looking at the fuel efficiency of the diesel this detail seems less dramatic. In the NEDC cycle the advantage amounts to 1.1 liters/100 km, while in real life auto motor und sport test’s revealed another figure: 1.8 liters. So, unless you are a taxi owner or fleet manager, choosing the Mercedes C 250 petrol engine is probably the better deal.
The 2-liter gasoline engine develops 184 HP and it leaves a long lasting impression in terms of refinement. And it is not only a question of the quieter operation, the C 250 is also in all situations the smoother, more keen to rev engine. Another : this mature character doesn’t depend on the quality of the fuel as it does in the diesel’s case.
The diesel engine, part of the OM 651 series, on the other hand, is good for 170 HP and has never been known for its exceptionally discreet manners. He is by no means a rough engine, but the characteristic vocal timbre becomes even more apparent in direct comparison to the civilised gasoline turbo. Hardly any differences in the driving performance, either. Even if the gasoline engine may not offer quite the same explosive torque, when accelerating it is a touch faster, while the top speed is practically equal. In addition, the C 250 is also cheaper to service than its diesel brother. Only if the annual mileage crosses the 30.000 kilometers mark, the diesel finally becomes the cheaper to run engine.
Conclusion: Advantage petrol
The C 250 is the more comfortable and more agile car in this comparison, although it requires almost two liters more fuel per 100 km on average. The smooth running nature and low maintenance costs make this disadvantage quickly evaporate, though.
Source: Auto motor und sport