IsItAGoodCar
Reliability Guide

Common Problems with the
2025 Audi Q8 (4M8)

We've identified 1 known issue that can affect the 2025 Audi Q8 (4M8). 1 of these are serious faults that could be expensive to repair.

1
Known Issues
1
Serious
0
Moderate
0
Minor

All Known Issues

TDI SCR / AdBlue System Faults

SeriousExhaust & Emissions

Diesel versions with SCR can develop dosing, heater or NOx sensor faults. A system fault may lead to a no-restart countdown even with sufficient AdBlue; diagnosis should distinguish fluid level from component failure.

Warning Signs:

AdBlue system warning, No-restart countdown

What to Inspect:
  • Check warning history and emissions repair invoices
  • Request a diagnostic check of dosing pressure, heater operation and NOx readings
Verified by IsItAGoodCar Research TeamUpdated

Buying Tips for 2025 Audi Q8 (4M8)

  • ✓Look out for 48V electrical system faults, specifically the Belt Starter Generator (BSG) failure, which will drain the battery and leave the car stranded; verify if it has been replaced under warranty.
  • ✓Test the dual-touchscreen MMI system thoroughly for responsiveness and ensure the haptic feedback works evenly across both screens.
  • ✓Check the frameless doors for excessive wind noise at motorway speeds, which may indicate worn weather seals or poorly aligned window regulators.
  • ✓Inspect the enormous alloy wheels (up to 23 inches) for kerbing and check tyre tread depth; replacing a set of premium tyres is exceptionally expensive.
  • ✓Ensure the adaptive air suspension adjusts smoothly between modes without sagging or throwing dash warnings, as replacing the complex struts is a huge expense.
  • ✓Verify that the automatic gearbox downshifts cleanly when slowing to a stop; some owners report clunky or hesitant downshifts that require transmission software recalibration.
2023–2024
Check a 2025 Audi Q8 (4M8) by Registration