Buick Lang Wei 20t accelerator has been cleaned at idle speed. Why is it getting lower and lower? What is the reason why the white gas in the exhaust pipe becomes bigger?

1, the most common cause of automobile jitter is that the throttle valve is too dirty or the fuel injector has too much carbon deposit;

2. When there is too much carbon deposit in the engine, the gasoline sprayed by the fuel injection head will be absorbed by the carbon deposit during the cold start, which leads to the lean mixture during the cold start and makes it difficult to start. In this case, the gasoline absorbed by carbon deposits will only be saturated;

It is easy to get into the car. After entering the car, the gasoline adsorbed on the carbon deposit will be sucked into the cylinder by the vacuum suction of the engine for combustion, and the mixture will become rich. The combustible mixture of the engine will be diluted and concentrated, which will lead to idling jitter after cold start.

4. Idle jitter is generally caused by carbon deposition inside the throttle and idle motor, which can be solved by cleaning the throttle and idle motor;

5. Poor gasoline quality leads to poor atomization effect of nozzle, and insufficient combustion of mixed gas in cylinder will also lead to idling jitter. It is suggested to use high-grade gasoline after using this box of gasoline and do a fuel system cleaning;

6. The spark plug does not ignite, resulting in one or more cylinders not working, and it will also lead to idle jitter. Check the ceramic part of the spark plug for cracks, and also check whether the ignition system is normal.