2017 Volkswagen Polo 1.2L Petrol · PA66 AAF

The latest MOT test in October 2025 initially failed due to elevated exhaust emissions, specifically excessive carbon monoxide, hydrocarbons, and an out-of-range lambda reading, which indicates a fuel mixture or combustion issue requiring immediate attention. The subsequent pass after rectification suggests the fault was addressed, but the recurrence of emissions failures in both 2024 and 2025 points to a persistent or underlying problem, possibly linked to a faulty lambda sensor, catalytic converter efficiency, or fuel system irregularities. The advisory history also shows a worsening trend in brake disc condition and suspension bush wear, with both front lower suspension arm bushes now flagged, alongside ongoing corrosion of the front subframe. This indicates a vehicle where maintenance has been reactive rather than preventative, with some components now approaching the end of their serviceable life. At 30,880 miles over nine years, the Polo has covered an exceptionally low annual average of around 3,431 miles, suggesting prolonged periods of inactivity or very light use. While low mileage can reduce wear on moving parts, it introduces risks associated with standing, such as fluid degradation, brake component corrosion, and sealing deterioration. The combination of age and minimal use means calendar-based maintenance, such as coolant, brake fluid, and transmission fluid changes, may have been overlooked, even if mileage-based service intervals were technically met. Additionally, tyres and rubber components can perish from age rather than wear, and the battery may suffer from deep discharge cycles if the car has stood unused for extended periods. Prospective buyers should prioritise a thorough inspection of the exhaust and emissions system, as the repeated MOT failures for high CO and hydrocarbon levels suggest the catalytic converter or oxygen sensors may still be marginal. Listen for rattling from the exhaust on a test drive, which could indicate a failing catalyst, and check for a sulphur or rotten egg smell, which often signals converter breakdown. The brake discs, flagged as worn, pitted, or scored in every MOT since 2023, should be visually inspected for deep grooving, lip formation on the edge, or uneven wear, and the car should be driven with attention to brake shudder or vibration under braking, which would confirm disc warping. The front suspension bushes, now advisory on both sides, may produce clunks or knocks over rough surfaces or when manoeuvring at low speed, and their condition should be checked for excessive play or cracking. Given the low mileage and age, also examine the tyres for sidewall cracking or crazing, particularly at the rear where advisories were noted in 2023, as aged rubber loses elasticity and integrity regardless of tread depth. Check the front subframe for significant corrosion, paying attention to structural rigidity and any signs of flaking or holes, as this can compromise safety. Verify the 12V battery health, as low-mileage cars often suffer from weak batteries due to insufficient charging cycles, and test all electrical functions, including lights and auxiliary systems. Finally, confirm the service history includes time-sensitive fluid changes, as brake fluid, for example, absorbs moisture over time, reducing boiling point and braking efficiency, and coolant degrades regardless of mileage, risking corrosion within the cooling system.