What is the reason why Volkswagen sagitar can't go to D gear but can refuel?

The possible reasons why Volkswagen sagitar can only be equipped with throttle instead of D gear are as follows: 1. The engine throttle is too small, and the fuel injection quantity of the injector is not enough. 2. There is something wrong with the control system and actuator signal of the gearbox itself, and the shift valve is not sensitive, resulting in the shift not being in place and the oil circuit not being opened. The following is an introduction to the related contents: Most automatic cars (especially those without AUTOHOLD function) step on the brake and put on the D forward gear after the engine starts. After releasing the brake, it will slowly move forward under the action of idle speed (just like the manual gear 1 gear), but the speed is slow, and the car will only accelerate if it continues to step on the accelerator.