P2106 fault code: Throttle Actuator Control System - Forced Limited Power Low severity

P2106 means “Throttle Actuator Control System - Forced Limited Power” — a vehicle speed & idle control fault in the powertrain. Safe to drive in most cases; stalling in traffic is the main safety concern. Typical UK repair cost: £25–£300 depending on the underlying cause.
LowSeverity
P21xxVehicle Speed & Idle Control
£25–300Typical UK repair cost
MOT fail riskif the warning light stays on

What does P2106 mean?

P2106 is a powertrain code from the extended SAE range reported by your car’s engine control unit. It sits in the P21xx block, which covers vehicle speed & idle control. The stored description is “Throttle Actuator Control System - Forced Limited Power”. The code itself tells you which circuit or system tripped the fault — not always the exact part that failed, which is why a short diagnosis pays for itself before replacing components.

Symptoms you may notice

  • Idle speed too high, too low, or hunting up and down
  • Stalling when coming to a stop
  • Cruise control not engaging

Most common causes

  1. Carbon-clogged throttle body or idle control valve
  2. Vacuum leak around the intake manifold
  3. Faulty vehicle speed sensor
  4. Throttle pedal or position sensor fault

How to diagnose P2106 yourself

  1. Clean the throttle body with throttle-safe cleaner
  2. Check for vacuum leaks with the engine warm
  3. Scan live throttle position and idle valve duty data
Tools that read and clear P2106

A basic code reader confirms the fault; a full-system scanner shows the live data you need for the steps above.

Will P2106 fail an MOT?

Not directly tested at MOT, but if the fault keeps the engine management light on, that light alone is a Major defect and a fail.

Before booking your test, check what usually fails on your car: see our MOT pass rates by make and model, built from 33.1 million DVSA tests.

Typical UK repair costs

OutcomeTypical cost (parts + labour)
DIY: read code + basic checks£0 (scanner assumed)
Independent garage diagnosis£30–£60
Typical repair range for this fault£25–£300
Main dealer equivalent£37–£540

Costs are indicative UK ranges for independent garages in 2026. Main dealers typically charge 40–80% more.

Diagnose the symptom, then price the repair

Car diagnostic test cost UK (2026): scan vs actual diagnosis£40–£100 is typical for an independent first assessment — but a code read is not the same as finding the cause.
P2100Throttle Actuator Control Motor Circuit/Open P2101Throttle Actuator Control Motor Circuit Range/Performance P2102Throttle Actuator Control Motor Circuit Low P2103Throttle Actuator Control Motor Circuit High P2104Throttle Actuator Control System - Forced Idle P2105Throttle Actuator Control System - Forced Engine Shutdown P2107Throttle Actuator Control Module Processor P2108Throttle Actuator Control Module Performance

P2106 — quick answers

Is it safe to drive with P2106?

Safe to drive in most cases; stalling in traffic is the main safety concern.

Will P2106 clear itself?

If the underlying fault stops occurring, most ECUs extinguish the light after around 40 healthy warm-up cycles — but the code stays stored as history. Fix the cause, clear it with a scanner, then confirm it stays away over a full drive cycle.

How much does it cost to fix P2106 in the UK?

Typically £25–£300 at an independent garage depending on which cause you confirm. Diagnosing it yourself with a scanner avoids a £30–£60 diagnostic fee and stops parts being replaced on guesswork.

Will P2106 fail my MOT?

Not directly tested at MOT, but if the fault keeps the engine management light on, that light alone is a Major defect and a fail.

Code definitions follow the SAE J2012 standard. MOT defect rules reflect the DVSA MOT inspection manual (2026). This page is general guidance for UK drivers, not a substitute for a professional diagnosis.