The intake pressure of the second generation engine of Chang 'an Star is 56, the cold car is turned off, and the exhaust pipe is black. What happened?

A simple EFI engine will adjust the fuel injection quantity according to the intake temperature, intake pressure (or intake volume), throttle opening and other parameters. If the intake pressure is high, the computer will mistakenly think that it is at the oil filler, so it will supply more oil. But if you don't open the throttle and increase the actual intake air, the mixture will be too rich, resulting in incomplete combustion and black smoke (sometimes it's just not obvious, but the three-way catalyst has been restored, but you have found it).

If the fuel supply is extremely cold, the engine may stall, and the engine will work unsteadily after a hot car, such as traveling.

First of all, we must find out the reason for the high intake pressure.