P2111 indicates that the throttle actuator control system has detected the throttle valve stuck in an open position, meaning the throttle plate cannot close as commanded by the engine control module. This condition prevents proper idle control and can trigger reduced‑power or limp‑home modes.
Deposits or wear can prevent the throttle plate from closing fully, causing the actuator to report a stuck‑open condition.
A malfunctioning TPS may send an erroneous open‑throttle signal even when the plate is closed.
Internal motor or gear damage can leave the actuator unable to move the plate to the closed position.
Corroded, broken, or shorted wires can disrupt the control signal and cause the system to interpret the throttle as stuck open.
An unintended vacuum leak can cause the throttle plate to be pulled open, though this is less common.
A rare internal failure of the engine control module could misinterpret throttle position data, but this is seldom the root cause.
Replacing the PCM is rarely necessary; the code is almost always caused by mechanical or sensor issues in the throttle body.
Yes, carbon buildup can prevent the throttle plate from closing fully, triggering the stuck‑open code.
Many vehicles require a throttle position relearn or adaptation after cleaning the throttle body or replacing a throttle component.
Typically the ECU will limit engine power, raise idle speed, or activate a reduced‑power mode to protect the engine.