2006 Audi A4 2.0L Diesel · PJ56 CNN

This 2006 Audi A4 presents a mixed but largely stable mechanical picture as of its most recent MOT on 24 November 2025 at 61,452 miles. The vehicle passed, yet the same cluster of minor advisories has persisted across multiple consecutive tests, indicating a pattern of tolerated deterioration rather than active remediation. The maintenance trend is stable but stagnant. A recurring oil leak, first noted in December 2023 and carried through both 2024 and 2025, remains within acceptable thresholds but points to a long-standing gasket or seal issue that has never been permanently addressed. Rear sub-frame and rear suspension arm corrosion, flagged as "not seriously weakened" since November 2024, suggests the vehicle has spent time exposed to road salt or moisture without underbody protection being renewed. Brake disc wear and surface pitting on the rear axle have been recorded consistently since the failed test of 1 December 2022, and a corrosive brake hose ferrule appeared in both 2024 and 2025. None of these items individually fail the test, but their persistence across three consecutive years signals a vehicle that has been maintained to a pass-only standard rather than a thorough one. The mileage profile is notably low for a vehicle approaching twenty years of age. At 61,452 miles, the annual average sits around 3,073 miles per year, which is well below the typical UK figure of 8,000 to 12,000. The progression from 56,999 miles on 1 December 2022 to 61,452 miles on 24 November 2025 represents roughly 4,453 miles over nearly three years, confirming very light use in recent years. The gap between the December 2022 pass at 57,003 miles and the December 2023 test at 58,676 miles shows only 1,673 miles covered in twelve months, reinforcing the impression of infrequent driving. Low annual mileage can preserve structural components from fatigue cycling, but it also means prolonged periods of standing, which accelerates rubber perishing, brake surface corrosion, and fluid degradation, all of which align with the pattern visible in this record. Prospective buyers should focus their physical inspection on the rear sub-frame and rear suspension arm mounting points, where corrosion has been flagged repeatedly. Surface corrosion noted as "not seriously weakened" in an MOT test does not guarantee structural soundness under load, and a thorough inspection with a torch and probe is warranted to check for pack rust or section loss hidden beneath underseal. The rear brake discs and hoses deserve close attention as well. Persistent pitting and scoring, combined with a corroding hose ferrule, suggest the rear braking system has been operating in a degraded state for at least three years. A road test should specifically check for uneven rear brake pull, binding, or a parking brake that holds inconsistently on gradients, echoing the inoperative nearside parking brake and binding service brake recorded in the December 2022 failure. The oil leak, consistently described as not excessive, should be traced to its source during any pre-purchase inspection. On a B7-generation A4 of this age, common origins include the camshaft cover gasket, the oil cooler seals, or the rear main seal. Left unresolved, even minor leaks can contaminate rubber hoses and accelerate corrosion on adjacent components, including the already flagged sub-frame area. Tyre condition and age should also be verified, as low-mileage vehicles often reach the legal tread limit on age rather than wear, and perished sidewalls are a common oversight on cars that stand for extended periods. Overall, this A4 appears mechanically sound enough to pass its MOT year after year, but the record reveals a vehicle that has been kept running rather than properly cared for, and a buyer should budget for addressing the accumulated advisories before they escalate into failures.