A European Cold-Weather Driveability Procedure

The cold-weather driveability performance of some European cars deteriorated in the early 1970s as a result of attempts to improve fuel economy and reduce exhaust emissions. Consequently, a test procedure was developed for rating the driveability performance of European cars equipped with manual chokes and manual transmissions so that the effects of ambient temperature and fuel volatility could be assessed. This procedure and its development are described and the effects of fuel quality, ambient temperature and engine hardware on the performance of European cars are discussed.