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Top 100 most fuel-efficient cars

Independent fuel efficiency and emissions figures produced for executive class cars

Mercedes E220 CDI

Want to save fuel and cut down your CO2 emissions? The DTI has just unveiled the “Act On CO2” initiative to encourage car buyers to purchase more fuel efficient motors. Auto Express has conducted its own research to find Britain’s 100 most economical motors.

The tests were conducted on public roads and take into account traffic conditions, weather, types of road and all the other variables that influence your mpg. Ten classes of cars were tested, from city cars to SUVs and family saloons to MPVs.

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Top of the executive chart was the Mercedes E220 CDI which managed to hold off the challenge of the BMW 525d by returning 37.1mpg. That was still 17 per cent behind official claims, though. The Citroen C6 almost matched the government’s figure of 32.5mpg, but that was only good enough for seventh spot.

Make/ModelTested MPG CO2
1. Mercedes E220 CDI37.1 167
2. BMW 525d35.6 165
3. Mercedes E280 CDI34.7 191
4. Volvo S80 D534.2 169
5. BMW 535d33.1 182
6. Jaguar S-Type 2.7D32.9 208
7. Citroen C6 2.7 HDi32.1 230
8. Audi A6 2.7 SE Multitronic31.5 192
9. Volvo V70 D5 SE29.7 209
10. Saab 9-5 2.0t BioPower27.8 244
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