What it means
The current draw of the throttle motor lies outside the expected range — either much higher (binding plate) or much lower (worn brushes, open winding) than calibrated.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
- The engine or gearbox may go into limp mode
How it works
The throttle actuator control motor moves the electronic throttle plate in response to commands from the engine control module. P2118 sets when the motor’s current draw falls outside the calibrated range for its operation, which can indicate excessive mechanical resistance or an electrical fault such as an open motor winding.
Common causes
Most likely first.
- Plate binding from carbon
- Motor windings aged or open
- Sensor element aged beyond calibration window
Symptoms
- Check engine light on
- Reduced throttle response, possible limp mode
- Hesitation or surging
- Idle too high or too low
How to diagnose it
- Record freeze-frame data and check commanded throttle position, actual position, and related actuator codes to see when motor current went out of range.
- Inspect the throttle motor connector and wiring for corrosion, heat damage, loose pins, or chafing that could interrupt or increase current flow.
- Check the throttle plate and bore for deposits or binding that could make the motor work harder; follow the vehicle maker’s guidance and do not force the plate.
- Use a scan tool’s actuator test, where supported, to compare commanded and actual movement and review motor current data.
- Test the motor circuit and actuator against the manufacturer’s specification to distinguish a wiring fault, a worn or open motor, and mechanical drag.
Common fixes
- Repair a loose, corroded, or damaged throttle motor connector or wiring.
- Clean throttle-body deposits if they are causing plate resistance.
- Replace the throttle body or actuator assembly if motor current or movement fails testing.
- Complete the specified throttle relearn after repair if the vehicle requires it.
Can I keep driving?
The engine may enter reduced-power mode or respond unevenly, so avoid high-speed driving and situations that require rapid acceleration. Continued operation with a binding throttle or failing motor can worsen the loss of throttle control.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.