P2118

Actuator Control Motor Current Range/Performance

P2118 is a generic OBD-II powertrain diagnostic trouble code: Actuator Control Motor Current Range/Performance. It is logged by the engine control unit when the scr/adblue monitor detects that a specific fault threshold has been exceeded — typically resulting in the malfunction-indicator lamp (MIL / check-engine light) being illuminated.

Code
P2118
Group
Powertrain
System
SCR/AdBlue
Severity
Warning (MIL on, possible limp mode)
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What P2118 means

P2118 is set when the ECM detects that the current draw of the electronic throttle body (ETB) actuator motor is outside the expected range for the commanded position. The electronic throttle control system uses a DC motor to open and close the throttle plate, with position feedback provided by dual throttle position sensors. The ECM monitors motor current to detect excessive mechanical resistance, a sticking throttle bore, or a motor that is drawing too much or too little current relative to the commanded effort.

This code differs from position sensor or actuator circuit faults in that the circuit is electrically functional but the motor's current consumption does not match the expected profile. Common causes include carbon buildup on the throttle bore restricting plate movement, a failing motor winding, or a mechanical jam caused by a foreign object or damaged return spring.

Because the electronic throttle is directly tied to driver demand and engine safety functions, most calibrations place the engine in a reduced power or limp mode when this code is active. The throttle may default to a fixed partial-open position, limiting vehicle speed significantly.

Common causes

Most-frequently reported root causes when P2118 is logged.

  • 1
    Carbon or varnish deposits on the throttle bore causing excessive mechanical resistance.
  • 2
    Throttle plate physically stuck or binding due to a damaged return spring.
  • 3
    Electronic throttle body actuator motor with degraded windings drawing abnormal current.
  • 4
    Foreign object lodged in the throttle bore obstructing plate movement.
  • 5
    Throttle body connector or wiring with high resistance causing intermittent current drop.
  • 6
    ECM driver circuit for the throttle motor beginning to fail.
  • 7
    Throttle body assembly damaged internally from impact or overheating.

Symptoms drivers notice

MIL illuminated, often with an electronic throttle control warning light.
Engine enters reduced power or limp mode limiting vehicle speed.
Throttle response is sluggish or erratic.
Engine may stall at idle if the throttle plate is stuck in a near-closed position.
Acceleration hesitation or surging under light throttle inputs.

How to diagnose P2118

A typical diagnostic flow when this code is present.

  1. 1
    Read all stored codes and record freeze frame data; note if any throttle position sensor codes accompany P2118.
  2. 2
    Inspect the throttle body for carbon deposits; attempt to rotate the throttle plate by hand with ignition off to feel for binding.
  3. 3
    Monitor throttle motor current using a scan tool's live data during a controlled throttle sweep.
  4. 4
    Inspect the throttle body wiring harness and connector for corrosion or damaged terminals.
  5. 5
    Clean the throttle body with an appropriate cleaner and retest if carbon buildup is found.
  6. 6
    Perform an electronic throttle body relearn procedure after cleaning if required by manufacturer.
  7. 7
    Replace the throttle body assembly if motor current remains out of range after cleaning and wiring checks.

Related powertrain codes

Frequently asked questions

Can cleaning the throttle body fix P2118?

Yes, if excessive carbon deposits are causing mechanical resistance; cleaning resolves the fault in many cases without part replacement.

Is P2118 dangerous to drive with?

Limp mode protects the engine but severely limits performance; diagnose promptly, especially if the vehicle stalls.

Do I need a relearn after replacing the throttle body?

Most vehicles require an idle relearn or throttle body adaptation procedure after replacement; consult the manufacturer procedure.

Can a dirty air filter cause P2118?

A dirty air filter alone rarely causes this code; P2118 is specific to the throttle actuator motor current, not airflow quantity.

Disabling P2118 in software

RaceTune can permanently disable P2118 — and any other OBD-II diagnostic trouble code — on every ECU family we support. The monitor is disabled inside the ECU itself, so the fault stops being logged: the warning light stays off and the engine never enters limp mode for this code. The change is tied to your exact software version.

Permanent
The monitor is disabled in the ECU itself — not just cleared. It cannot return.
Tailored to your file
Each patch is matched to your specific software version — never a one-size-fits-all file.
Reversible
The original file is always preserved. Reflash the stock to return the ECU to factory state.

Software modifications affect emissions compliance and are not road-legal in many jurisdictions. RaceTune service files are intended for motorsport, off-road, and export use.

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