Cold weather engine warm

In addition to the above, higher-cetane-number fuels tend to result in easier starting, particularly in cold weather, and faster warm-up. The higher-cetane-number fuels also usually form softer and hence more readily purged combustion chamber deposits and result in reduced exhaust smoke and odor. High-speed diesel engines normally are supplied with fuels in the range of 45-55 cetane number. 

The example chosen was described by Coates and was concerned with the spectra of gasoline samples. At the change of season, the composition of gasoline is also changed to provide better engine performance in cold versus warm weather. 

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