CKFCar Known Faults
MinorAffected: 2009-201750,000–120,000 miles

Volkswagen Polo Mk5 1.4 85bhp — Throttle Body Failure

Throttle body contamination and electronic throttle actuator failure cause hunting idle and poor response on the 1.4 Polo. A common and inexpensive fix if caught early.

Severity

Minor

DIY Difficulty

Easy

Est. Cost

£50–£300

OBD Codes

P0506P0507P0122
Component Diagram

Engine

Typical layout and location for the Engine assembly.

Engine diagram
Reference Illustration

Symptoms

  • Hunting or fluctuating idle
  • Hesitation under light throttle
  • Limp mode in severe cases
  • P0506/P0507 or P0122 codes

Root Cause

Oil vapour from the PCV system coats the throttle blade over time. The electronic throttle actuator motor can also develop faults independent of contamination.

How To Fix

  1. Clean throttle body with carb cleaner — cheap first step
  2. Perform throttle body adaptation via VCDS or OBD after cleaning
  3. Replacement throttle body if motor has failed: £80-150
  4. Fitted: £150-300

Estimated Repair Costs

Repair OptionEst. Cost (GBP)
DIY (parts only)£20–£120
Independent Garage£50–£300
Main Dealership£80–£480

Other Faults on This Variant

Timing Chain Rattle on Cold Start

Moderate
2009-201770,000–140,000 miles£400–£700

The 1.4 petrol Polo uses a timing chain, but the tensioner weakens with age causing a cold-start rattle. Left unchecked, chain stretch causes valve timing issues.

Coil Pack and Ignition Failure

Moderate
2009-201750,000–120,000 miles£50–£200

Coil pack failure on the 1.4 Polo causes misfires and rough running. Individual coil packs are inexpensive but the fault can be mistaken for more serious engine problems.

Disclaimer: Repair cost estimates are indicative and based on community data. Always get a quote from a qualified mechanic before proceeding with any repair.