The connecting screw between throttle and manifold is broken.

The installation of the three screws has no effect, but the vacuum degree of the intake pipe increases during the rapid acceleration, and there will definitely be inhalation. The mixture will be diluted, resulting in insufficient engine power. When idling, the impact should be small. After all, when idling, the air intake is limited, and the internal pressure is not enough to cause air leakage.

Personally, please forgive my shortcomings.