2018 Citroen C4 1.2L Petrol · WN18 RLX

The defining mechanical story behind this 2018 Citroen C4 is one of chronic underbody and rear-end wear, with no fewer than four separate MOT failures recorded across the last three years and a recurring theme of deteriorating rear suspension, exhaust integrity, and tyre condition. The most recent test on 11 December 2025 produced a pass with no advisories, which on the surface looks tidy, but this must be set against the same date's failed attempt for an offside stop lamp and a December 2024 failure that was genuinely concerning. That 2024 test recorded a dangerous nearside rear tyre below the legal 1.6mm tread limit, a major exhaust gas leak at the rear, an out-of-specification lambda reading, and an advisory for worn rear brake discs, while a March 2024 failure added a fractured nearside rear coil spring. Earlier still, March 2023 flagged up lamp intensity issues and a reversing lamp failure. Taken together, the trajectory is not one of steady decline so much as a recurring cluster of advisories and majors concentrated on the rear axle and underside, and any prospective buyer should treat the clean December 2025 pass as a snapshot rather than proof of underlying structural health. The usage profile raises further questions. At 112,015 miles across roughly eight years, this C4 is accumulating around 14,000 miles annually, which is notably high for a car of this age and sector. MOT records span from March 2023 through December 2025 with relatively tight gaps and no obvious lay-up periods, suggesting the vehicle has been in regular, hard-driven use rather than left standing. Higher annual mileage of this kind accelerates wear on suspension bushes, coil springs, brake discs and pads, tyres, exhaust mounting rubbers, and drivetrain mounts. The fact that the recorded defects align with exactly these consumable and chassis components is consistent with the mileage rather than indicative of any isolated fault. The 2024 test in particular flagged a fractured rear coil spring alongside scored rear brake discs and a rusty exhaust, all of which are textbook high-mileage wear items, and the tyre failures suggest the previous keeper was either unaware of rear axle deterioration or was running the car close to the legal edge on tread depth. For a buyer walking up to view this C4, the rear axle and underbody should be the absolute priority. On a test drive, listen carefully for clonking or knocking noises from the rear over speed humps and uneven surfaces, which would indicate tired rear suspension bushes or a further weakened coil spring following the 2024 fracture. With the car jacked or on a ramp, inspect the rear coil springs in person for any cracking or sagging, check the exhaust system from the catalytic converter back for black soot deposits around joints or hangers indicating active leaks, and examine the rear brake discs for a pronounced lip on the outer edge and any pitting visible through the wheel spokes. Because a lambda sensor reading was out of specification in 2024, pay attention to any smell of unburnt fuel, rough idle, or hesitation under acceleration, which could suggest the lambda sensor or a downstream oxygen-related fault has returned. Also verify all rear lighting works correctly, including the offside stop lamp and reversing lamp, both of which have failed in recent tests. Finally, do not neglect the wheels and tyres. The offside front wheel was noted as slightly distorted in both 2023 tests, and although it was not flagged again in 2024 or 2025, a distortion of this kind can persist and cause vibration through the steering at higher speeds, so test the car on a motorway-style road and feel for any steering wheel tremor between 60 and 70 mph. Check all four tyres for uneven shoulder wear, which often points to suspension geometry or bush wear on the rear axle, and confirm that the tread depth is comfortably above the 1.6mm legal minimum rather than simply legal. Given that an advisory for a distorted wheel, a fractured rear coil spring, scored brake discs, and a leaking exhaust have all surfaced within the last three MOT cycles, a pre-purchase inspection by an independent garage with the car on a lift is strongly advisable before committing to purchase.