What is the reason for the shaking of Audi A6L 2.0T cold car?

I like to say first, second and third.

First, there is too much carbon deposition in the throttle, which leads to insufficient air intake when the car is cold and poor combustion in the cylinder, which leads to engine jitter and unstable idle speed! So, see if the accelerator has been washed recently. It should be washed at 15000KM.

Second, the poor quality of gasoline and insufficient combustion lead to carbon deposition on the piston surface and the edge of high-pressure nozzle. So the cold car began to burn badly and the carbon deposit was too hard. Usually, it is best to warm the car. The solution is to change gasoline, or add fuel additives, and then clean the oil circuit!

Third, this is a unique problem of 2.0T, which is that the exhaust gas recirculation valve is damaged, resulting in vehicle jitter. However, this situation exists when the vehicle is hot or cold. The inspection method is that when the vehicle is idling, you can unscrew the fuel filler by hand to see if it can be easily opened. If it is followed by a sucker, it is broken. Just change it. It should only have a little suction. It can be opened easily.

Well, that's what I thought. I guess it's just the first two love issues.