2018 Audi A6 3.0L Diesel · S3 COF

The 2018 Audi A6 presents a mixed maintenance picture, with a clear downward trend in its most recent testing cycle. On 18 June 2025 at 92,661 miles, the car first failed with an engine MIL inoperative or indicating a malfunction, alongside worn and pitted front brake discs and thin front brake pads. A retest on the same day at the identical mileage passed, suggesting the MIL and brake issues were addressed, yet the underlying pattern is concerning. Two consecutive advisories on front brake discs and pads in 2025, after years of clean tests, indicate accelerated wear that demands scrutiny. The maintenance trajectory has shifted from stable to worsening, with the powertrain warning light raising questions about engine management health. The mileage accumulation of 92,661 miles over roughly eight years equates to approximately 11,583 miles annually, which is typical for this age and class of vehicle. The record shows a notable jump from 76,405 miles on 8 July 2024 to 92,661 miles by 18 June 2025, representing 16,256 miles in under twelve months. This sharp increase suggests heavier use in the most recent year, potentially placing additional stress on consumable components such as brakes, tyres, and suspension bushes. Prior to that, the annual increments were more moderate, rising from 49,415 miles in June 2022 to 61,754 miles in June 2023 and then to 76,405 miles in July 2024, each step reflecting roughly 12,000 to 14,000 miles per year. A buyer should focus a physical inspection on the front braking system, given the repeated advisories. The pitted and scored front brake discs flagged in 2025 suggest either aggressive driving, a dragging caliper, or prolonged use beyond safe thickness. Check for uneven disc wear, caliper slide pin seizure, and pad retention hardware condition. The engine MIL fault, though cleared for the retest, warrants a full OBD scan to retrieve stored fault codes and verify that the issue was not simply a bulb or circuit fault masked rather than resolved. Inspect the exhaust system for leaks that could affect lambda sensor readings and emissions compliance. Beyond the flagged items, examine the suspension bushes, coil springs, and drop links for wear, particularly given the mileage surge in the last year. Structural corrosion around the subframes, inner wing arches, and sills should be probed, as Audi models of this generation can develop corrosion in hidden areas. Verify tyre condition and tread depth across all four corners, and check for any uneven wear patterns that could indicate alignment or suspension geometry faults. The MOT record is sparse on deeper mechanical items, so a compression test and inspection of the dual-mass flywheel and gearbox for play or noise would add valuable confidence before purchase.