صفيحة الخنق عالقة مغلقة

The throttle plate held shut so it cannot open to the commanded position. It is the opposite failure to a plate stuck open, and although both are a seized throttle the consequences differ completely: this one limits power rather than adding it.

The engine may idle acceptably and refuse to make power, since idle needs only a small opening and the plate is closest to correct there. The complaint is a vehicle that starts and runs but will not accelerate, with a throttle actuator code reporting a position not achieved — and the driver often describes it as a total loss of power.

Carbon at the plate's edge is the usual cause, along with a foreign object, a bent plate, or ice in cold damp conditions. Check the plate opens fully and freely by hand with the ducting off, and note that a relearn is required after any cleaning — the module has adapted to the old closed position, and removing carbon moves it.