Audi SQ8

Excessive DPF regeneration events allow diesel fuel to enter the engine oil, causing the oil level to rise. A known problem with no permanent fix — regular oil level checks are essential.

Symptoms: Rising oil level, oil level above maximum, slight increase in consumption, occasional diesel smell from engine bay

The electrically driven auxiliary compressor of the 48V system fails at higher mileages. The symptom is poor throttle response in the low rpm range. Repair is complex.

Symptoms: Poor throttle response on take-off, power loss below 2,000 rpm, engine management warning light

Intake manifold and tumble flap coke up from blowby gases and EGR. Cleaning sometimes requires a full engine removal; repair costs are therefore very high. Primarily affects short-trip vehicles.

Symptoms: Power loss, poorer throttle response, increased fuel consumption, rough running

The diesel particulate filter does not fully regenerate with frequent short-trip driving. Blockage requires a forced regeneration at a workshop or expensive DPF replacement.

Symptoms: DPF warning light, power reduction, increased fuel consumption, stationary engine regeneration

Faulty sensors in both front doors can affect side airbags, head airbags and belt tensioners. RAPEX notification INFO/00089/21, April 2021. Free repair at authorised dealer.

High-voltage battery cell modules can overheat when charging and cause a vehicle fire. KBA action 93QQ affects Q8 PHEV (60 TFSI e) from production period 08/2019–07/2024. Software update as fix, approx. 60 minutes workshop visit.

Oil can leak from the automatic gearbox cooling lines. Gearbox oil on the road increases accident risk. NHTSA campaign 20V272000, 531 vehicles affected.

On Q8 models from 2019–2021 (action 42L1) an incorrectly torqued rear axle nut can alter wheel alignment and affect driving stability. Free repair at dealer.

The Q8 4M air suspension shows typical weaknesses on residual pressure hold valves (approx. 50 € part) and air bags. Warning light illuminates, vehicle drops on one axle, compressor runs continuously to the point of overheating.

On the SQ8 4M the upper centre console display frequently goes black. The lower climate control display flickers. The problem occurs sporadically and cannot be resolved without restarting the system.

During fast motorway driving above 120 km/h the SQ8 4M can display air suspension warning lights and temporarily lose ride height until the compressor catches up. Pressure sensor and leak warnings occur sporadically.

The SQ8 4M with 48V mild-hybrid system is potentially susceptible to BSG failures like other C8/4M platform vehicles. Audi granted a 7-year extended warranty on the component.