2016 Mercedes-Benz C 4.0L Petrol · DF66 XSP

The most recent DVSA examination on 30 March 2026 produced a Pass with no defects recorded, however the identical date also carries a Fail notice issued for two Major exhaust emissions defects relating to carbon monoxide content exceeding the manufacturer's specified limits at both idle and after the second fast idle. Because the Pass and Fail share the same date, the most plausible sequence is that the vehicle was presented, failed on emissions, rectified, and re-presented the same day to secure the pass certificate. Provided the remedial work actually addressed the root cause, the overall maintenance trend from the historical record remains broadly stable. Every prior MOT between 2019 and 2025 returned a clean pass with no advisories, indicating that the vehicle has consistently met roadworthiness standards throughout its life. The isolated emissions failure therefore needs to be treated as a one-off incident rather than evidence of systemic deterioration, but it warrants specific verification before purchase. The recorded mileage of 12,269 miles against a 2016 build year equates to an annual average of roughly 1,200 miles, which is exceptionally low and well beneath typical usage for a C-Class of this age. The MOT record itself does not reveal a mileage entry for the 2023 test, suggesting either a missed test or a deliberate gap in annual mileage progression, both of which are common when vehicles are used sparingly or stored for periods. Such low mileage raises mechanical considerations beyond the MOT data: prolonged standing leads to binding brake calipers, surface corrosion on brake discs, oxidation of internal engine components, degradation of oil seals and gaskets, and flat spots or perishing in tyres that have not been regularly rotated. The very low annual usage also implies that time-based deterioration rather than wear from distance is the dominant factor affecting consumables, so age-related checks should take priority over mileage-based expectations. Although the MOT history is largely free of recorded advisories, the recent emissions failure should be questioned directly with the seller. Request documentation of the repair, whether the lambda sensors were checked or replaced, and whether the catalytic converter was inspected or renewed, as elevated carbon monoxide readings are frequently attributable to a failing oxygen sensor, deteriorated catalytic converter, vacuum leak, or degraded spark plugs and ignition coils. On a test drive, listen for irregular idle, misfires under acceleration, hesitation, or any smell of unburnt fuel from the exhaust, all of which could indicate that the emissions issue has not been fully resolved. Cold-start behaviour warrants particular scrutiny given the low usage, as a vehicle that has stood for extended periods can develop oil leaks around valve cover gaskets and camshaft seals that only become apparent once the engine warms up. Given the low mileage and ten-year age, a prospective buyer should carry out several physical inspections that fall outside MOT scope. Examine the tyre sidewalls carefully for cracking, perishing and crazing associated with age rather than tread wear, and confirm the production date code on each tyre sidewall as tyres older than six years should be replaced regardless of remaining tread. Check the 12 volt battery state of health, because batteries that have been left in a partially discharged state suffer accelerated internal degradation and Mercedes-Benz vehicles are particularly sensitive to voltage drops that trigger electronic control unit errors. Inspect the brake discs for severe edge corrosion and confirm the calipers release cleanly by confirming the wheels rotate freely by hand when cold. Finally, verify that brake fluid, coolant and automatic transmission fluid have been changed on a calendar basis rather than purely by mileage, as all three degrade hygroscopically or chemically with time; Mercedes-Benz generally prescribes brake fluid renewal every two years and coolant changes at regular intervals regardless of distance covered, and confirmation of these services through the service book or independent invoices is essential on a vehicle of this age and usage profile.