IsItAGoodCar
Reliability Guide

Common Problems with the
2011 Toyota iQ (AJ10)

Interior and powertrain enhancement for the 2011 model year. Introduced softer-touch dashboard surfaces, revised door trims, updated Euro 5 emissions calibration for the 1.0-litre engine, and broader availability of the flagship 1.33-litre Dual VVT-i four-cylinder engine with Stop & Start.

What changed for 2011

  • •Upgraded interior dashboard plastics and higher-quality door cards
  • •Euro 5 emissions compliance across all 1.0-litre and 1.33-litre engine choices
  • •Stop & Start system fitted as standard on manual 1.33-litre Dual VVT-i models
  • •New exterior paint options and fresh alloy wheel finishes

Common MOT watch-outs

  • !12V auxiliary battery weak voltage causing Stop and Start system failure
  • !Front suspension strut top mount bearing binding when turning
  • !Rear brake drum shoe wear and parking brake cable stretch
3
Known Issues
0
Serious
3
Moderate
0
Minor

All Known Issues

1.0 1KR-FE EGR Valve Carbon Clogging and Engine Stalling

ModerateEngine

Urban-driven 1.0-litre three-cylinder models suffer from heavy soot and carbon buildup within the exhaust gas recirculation (EGR) valve and intake manifold channels. Persistent short urban trips prevent the engine from reaching self-cleaning temperatures, causing the valve pintle to stick open. This introduces unmetered exhaust gas into the intake charge at low rpm, causing rough hunting idle, jerking under light throttle, and unexpected engine stalling when stopping at junctions.

Est. Repair Cost: £150–£350
Warning Signs:

Engine stumbles, hunts, or stalls completely when dipping the clutch and slowing to a halt, Erratic idle speed fluctuating wildly between 500 and 1,100 rpm when stationary, Check engine warning light illuminated on the dashboard with fault code P0400, Hesitation and momentary stuttering when gently pressing the accelerator from rest

What to Inspect:
  • Allow the vehicle to idle for five minutes following a warm test drive and verify idle speed remains solid at 800 rpm
  • Drive at low speeds in second gear, dipping the clutch suddenly to ensure the engine recovers smoothly without stalling
  • Check service invoices for previous EGR valve cleaning or replacement by a franchised dealer
Verified by IsItAGoodCar Research TeamUpdated

Electric Power Steering EPS ECU Calibration and Steering Knock

ModerateSteering

Early 2009–2010 models can develop an intermittent knocking sensation or sudden temporary loss of power steering assistance. The electronic power steering ECU control logic was overly sensitive to voltage interference from the alternator when navigating sharp bumps, causing the control module to disconnect steering motor assistance and illuminate the P/S warning lamp. Toyota issued UK safety recall R/2010/181 to reflash the EPS ECU software.

Est. Repair Cost: £100–£300
Warning Signs:

Amber P/S power steering warning light illuminates intermittently on the instrument cluster, Steering wheel suddenly feels heavy and resistant when turning tightly in car parks or mini-roundabouts, Dull knocking sound and vibration felt through the steering column when driving over rough road surfaces, Steering assist cuts out momentarily when driving over sharp road expansion joints

What to Inspect:
  • Turn the steering wheel smoothly lock-to-lock while parked with engine running to confirm consistent assistance
  • Verify on the GOV.UK vehicle recall database that EPS software recall campaign R/2010/181 was carried out
  • Listen for clicking or play in the lower steering column intermediate shaft joint
Verified by IsItAGoodCar Research TeamUpdated
Official Recalls & Reference Documents:

Multidrive CVT Automatic Transmission Judder on Take-Off

ModerateGearbox & Transmission

The optional Multidrive continuously variable transmission (CVT) can develop a noticeable shudder and hesitation when setting off from a standstill, particularly on upward gradients. The fault stems from degraded CVT fluid, contaminated solenoid valves within the hydraulic valve body, or slippage of the steel drive belt across the variable pulleys due to missed fluid changes.

Est. Repair Cost: £250–£750
Warning Signs:

Pronounced vibrating judder transmitted through the driver seat and floorpan when pulling away gently, Hesitation of several seconds followed by sudden harsh lurch when pressing the accelerator pedal, Whining noise from the transmission casing that increases with road speed in town driving, Transmission flares revs without corresponding vehicle acceleration on hills

What to Inspect:
  • Conduct several gentle and brisk pull-aways from a dead stop on an incline to check for belt judder
  • Select Reverse on a slope and ensure immediate smooth engagement without delay or thumping
  • Review service history receipts for genuine Toyota CVT Fluid TC or FE changes
Verified by IsItAGoodCar Research TeamUpdated

Buying Tips for 2011 Toyota iQ (AJ10)

  • The 2011 interior refresh resolves complaints about hard cabin plastics on early cars
  • The 1.33-litre model provides noticeably greater motorway cruising refinement
  • Check that the rear seat folding latches and luggage cover bag are present and undamaged
20102012–2014
Check a 2011 Toyota iQ (AJ10) by Registration