There are many causes of black smoke failure, if the carburetor is black smoke, the reason is more complex. For example, during cold start, the spark plug is not good, want to play half a day to start the motor, so the mixture in the cylinder volume is not completely burned, naturally there will be black smoke; or vehicle ignition at the wrong time, before or after the fault will cause smoke generation. EFI cars generally emit black smoke rarely, if the smoke really appeared, it is mostly in the cylinder body failure. "Broken cylinder" is a common one.

Treatment methods：

1. carburetor car now basically on the age, to always check the carburetor and other parts of the aging degree, carburetor car is different from EFI car, to regular maintenance and adjustment, to develop good car habits.

2. EFI cars should be checked every 30 thousand kilometers cylinder line, every 10 thousand kilometers to check spark plugs, problems should be replaced in time.