Audi A6
EA189 derivative (105 PS) in the A4 B8. All EA189 vehicles are affected by the VW diesel emissions scandal and received the mandatory software update. The update triggered EGR issues in some cases. Main weak points: EGR valve, water pump, and DPF with short-trip use.
Worry engine — costly weakness looms
163 hp 2.0L with a known issue: EGR valve coked and blocked. The risk of expensive repairs overshadows any driving pleasure.
Engine Weaknesses 6
After the emissions-scandal software update, injector failures on the EA189 increased. Multiple injectors are often affected in succession. Costly damage.
Symptoms: Rough engine, misfires on individual cylinders, engine warning light, heavy judder on acceleration, increased fuel consumption.
The CGLC 2.0 TDI 177 hp shows critically low oil pressure at hot idle (>100°C oil temperature). Bearing clearances in the cylinder head are the root cause. Below 0.8 bar at idle, bearing damage is imminent.
Symptoms: Oil pressure warning at hot idle, red oil pressure warning symbol, engine noises at low rpm.
EA189 EGR valve carbons up from soot deposits, especially with short trips. Complete unit including cooler often needs replacing. Cost €700–1,281.
Symptoms: Engine warning light, power loss, judder on pull-away, increased fuel consumption, occasional limp mode.
On the EA189 2.0 TDI the water pump can fail prematurely leading to sudden coolant loss. A failure often also necessitates a timing belt change.
Symptoms: Coolant warning on display, rising temperature gauge, coolant loss; in worst case, overheating engine damage.
The diesel particulate filter clogs with frequent short-trip use because regeneration temperature is never reached. Cleaning or replacement required.
Symptoms: DPF warning light on, power drop, increased fuel consumption, sluggish engine or reluctant to start.
The CGLC 2.0 TDI 177 hp regenerates the DPF too frequently, causing fuel entry into the engine oil. Oil level rises, lubrication effectiveness decreases.
Symptoms: Engine oil change warning, oil level rises, fuel smell from oil filler cap, frequent DPF warnings.
Vehicle Weaknesses 8
On model years 2015–2018, the locking bolt of the tow bar can fracture, potentially causing the trailer to become detached while driving. Free workshop visit required.
A material defect can cause the camshafts in the 3.0 TDI to fracture, leading to engine damage. Mainly affects vehicles from model year 2014 to early 2017.
The optional air suspension (AAS) is prone to failure through porous air bellows and defective compressors. Repair costs of 600–1,800 EUR per corner are possible.
LED headlights fail due to defective control modules or individual LEDs. Repair is often more expensive than replacement, as modules cannot be replaced individually.
The automatic climate control shows malfunctions from around 60,000 km: incorrect temperature regulation, blower stage issues or complete failure of individual zones on the three-zone system.
Wheel bearings, particularly at the rear axle, show increased wear at higher mileages. Regularly flagged on vehicles from 80,000 km.
On the C7, rust occurs primarily on the underbody and sills, sometimes in hard-to-reach areas. On vehicles over 7 years old, the underbody should be thoroughly inspected.
On V6 and V8 engines, engine mounts often wear from around 50,000 km, causing noticeable vibrations.