BMW x5 fault code 55000. The car will stall when it starts cold.

1. The spark plug loses its ignition ability.

2. There is something wrong with the throttle. The above two problems will cause engine jitter and unstable speed.

3. Carbon deposition will cause insufficient combustion of gasoline, leading to engine jitter. The influence of engine carbon deposition on automobiles is considerable. First, the engine power is reduced, that is, the power output is uneven and gradually decays, in other words, it is getting less and less powerful. The second is to increase fuel consumption and increase your economic burden. Third, it is difficult to start a cold start, that is, it is difficult to strike a fire and it is not easy to get a taxi. Finally, serious carbon deposition in the combustion chamber will also lead to cylinder knocking, and low-speed acceleration will make noise, which will damage the piston and crankshaft, lead to engine heating, and seriously affect automobile safety. Then the discharge exceeds the standard, which not only fails the annual inspection, but also directly aggravates the harm of environmental pollution.

4. The load operation of gearbox will destroy the quality and friction characteristics of gearbox oil, increase friction and wear, and the noise of gearbox will follow. At the same time, sludge (impurities or dirt) will also be produced in the gearbox (such as the valve body), which will lead to the gearbox's frustration, gear shifting, impact, slipping, flameout, abnormal sound, delay, high temperature and oil leakage. (Audi and other high-end models will call the police and enter the gearbox protection mode. If it is not solved in time, the gearbox will be scrapped.