Why does car stall when shifting from drive to park?

A car may stall when shifting from drive to park due to several reasons, including a sudden change in engine load, which can disrupt the idle speed. If the engine is already running roughly or the idle speed is too low, the transition can cause the engine to stall. Additionally, issues with the transmission, such as low fluid levels or mechanical problems, can affect the car's ability to shift smoothly. Lastly, engine management system faults could also lead to stalling during gear shifts.