Fādòngjī de mópiàn pòliè le, suǒyǐ yālì shàng bù qù.
The engine's diaphragm is cracked, so the pressure won't build up.
Tips
usage
膜片 is the component-level word (diaphragm in a fuel pump, speaker, pressure sensor, microphone). For the general concept of a membrane or thin film, use 膜 alone; 膜片 specifies a discrete disc-shaped part.
