3.0 TDI Timing Chain Rattle
SeriousEngineThe V6 TDI timing chains sit at the rear of the engine and the hydraulic tensioners can weaken, causing cold-start rattle and potential chain jump if ignored.
Est. Repair Cost: £1,500–£3,000
Reliability GuideCommon Problems with the
Common Problems with the
2018 Audi A6 Mk4 (C7)
We've identified 4 known issues that can affect the 2018 Audi A6 Mk4 (C7). 2 of these are serious faults that could be expensive to repair.
4
Known Issues
2
Serious
2
Moderate
0
Minor
All Known Issues
Adaptive Air Suspension Leak
SeriousSuspension & ChassisCars with optional adaptive air suspension develop leaks in the air struts, causing the car to sag and the compressor to overwork and fail.
Est. Repair Cost: £700–£2,000
DPF Clogging and Regeneration Issues
ModerateExhaust & EmissionsTown-driven 3.0 TDI models block their DPFs, causing warning lights, limp mode and expensive DPF cleaning or replacement.
Est. Repair Cost: £250–£1,200
Electrical Module and Sensor Faults
ModerateElectrics & ElectronicsVarious electrical issues including MMI glitches, parking sensor failures, steering lock module faults and battery drain from comfort module issues.
Est. Repair Cost: £0–£600
Buying Tips for 2018 Audi A6 Mk4 (C7)
- ✓Check for coolant leaks in the "V" of 3.0 TDI engines
- ✓S tronic (DSG) models need fluid changes every 38k miles
- ✓Listen for humming from the front wheels (wheel bearings)