Audi A4
V6 diesel with 160 kW and enormous torque. Excellent long-distance engine. Timing chain — watch the tensioner. Service AdBlue system regularly.
Refined multi-cylinder — relaxed cruising
218 hp 3.0L with a pleasant, refined character. Relaxed long-distance cruiser without sporting ambitions. Factor in the known weak points.
Engine Weaknesses 5
Certain EA897 variants (3.0 TDI, 2014–2017) show a material defect on the camshafts. Cam lobe surfaces crack and valves no longer open correctly. Repair costs €3,500–20,000.
Symptoms: Ticking / knocking when cold, rough running, power loss, MIL, grinding noise in head
The 3.0 TDI CNHA uses four thin timing chains (one per cam bank, plus connector and oil pump chain), all on the gearbox side. Replacement costs €3,000–5,000 and requires 15–20 labour hours.
Symptoms: Rattling on cold start, camshaft control fault codes, oil pressure drop
The EGR system on the 3.0 TDI CNHA cokes up with heavy urban use. A failed EGR valve and coked EGR cooler module cause power loss and elevated emissions. Cleaning or replacement required.
Symptoms: Power loss, black smoke, stumbling under acceleration, increased consumption
The DPF on the 3.0 TDI does not fully regenerate during frequent short trips. Result: clogging and limp mode. Forced regeneration via an extended motorway drive or in-workshop procedure required.
Symptoms: DPF warning light, power reduction, increased fuel consumption, oil diluted with fuel
The NOx sensor on the 3.0 TDI CNHA cokes up and gives false readings. Typical: AdBlue system fault despite a full tank. Sensor can be cleaned (carb cleaner) or must be replaced (€200–400).
Symptoms: AdBlue warning light, SCR system fault, elevated NOx readings, engine check light
Vehicle Weaknesses 7
Defective coolant valves cause coolant loss that can silently lead to overheating. Temperature sensors and thermostat housing are a weak point from 60,000–100,000 km.
The rubber bushings in the upper control arms wear prematurely, in some cases from as early as 60,000–80,000 km. The issue is said to have been fixed only with the 2019 facelift.
Certain 19-inch tyre combinations on the B9 lead to premature wear on the inner flanks. The cause is a suspension setup not optimally tuned for larger wheels. Regular wheel alignment recommended.
The S tronic dual-clutch gearbox judders when pulling away and at low speeds. The mechatronics unit can become defective.
Water pump and thermostat housing typically fail between 60,000 and 170,000 km. A well-known weak point on the 2.0 TFSI and 2.0 TDI.
The S tronic dual-clutch gearbox exhibits a known juddering in D and R at idle that Audi classes as within the state of the art. Diesel variants may additionally creep.
The MMI infotainment system frequently exhibits Bluetooth connectivity problems in facelift models: choppy music playback, missed ringtones. Software updates do not always provide a permanent fix.