What Car? True MPG, in association with Tesco Petrol Filling Stations, tests cars on real roads in exactly the same conditions that every motorist faces every day.
Until now, says Haymarket, the only information that’s been available is the car makers’ own figures, which are determined under EU law and are conducted in laboratory conditions on rolling roads. Not anymore. Car buyers can simply log on to www.whatcar.com/truempg and work out the fuel economy they can expect to get from their next new car using “our exclusive True MPG tools”.
“With rising fuel prices, the miles-per-gallon issue is high on every motorist’s agenda. Countless car buyers are frustrated that they don’t match the official government fuel figures. True MPG will allow motorists to select a car personalised to their driving needs and budget. We hope that it will become invaluable in the complex and emotional car-buying process,” said What Car? editor-in-chief Chas Hallett.
What Car? tests the vehicles using a portable emissions-measurement system when the engines have reached normal operating temperature. The vehicles are then driven by two experienced engineers over a variety of roads including motorway, A- and B-roads, and through towns and villages. The data from the testing considers driving style, changes in altitude, ambient temperature and humidity and engine temperature.
The state-of-the-art testing equipment is manufactured by Sensors Inc and is well proven globally. It has been used by vehicle and equipment manufacturers for both product development and testing.
The principle component of the testing equipment is a gas analyser, which measures carbon dioxide output (from which the g/km figure is derived). The equipment simultaneously captures carbon monoxide, nitrous oxide, nitrogen dioxide and optionally total hydrocarbons. From the carbon dioxide output and knowledge of the exact fuel in the tank, the fuel consumption in miles per gallon can be calculated via the mass balance method with a high degree of accuracy.
Throughout each test, the output of each gas is captured at intervals of one second, together with the engine performance readings from the engine control unit via the CANBUS. Further, a high-grade GPS unit and weather probe capture these readings at the same frequency.
What Car? has helped Britain’s car buyers make purchasing decisions for more than 35 years, and its tests are widely regarded as the most trusted source of new-car advice, concludes Haymarket.
