It suddenly got quite cold in Shanghai, and what happened: many buses and garbage trucks could not drive anymore. During summer they are using a cheap kind of diesel, that can only be used at temperatures above zero degrees. Because the temperature dropped so quickly they did not have time to change to better diesel, and even if they had the time most gas stations did not have it in stock. One of the few station that carried it had two-hour waiting lines to fill up the tanks of waiting vehicles. But soon the garbage trucks will drive around again, as temperatures gradually go up again to about 12 degrees.