The drain channels of the panoramic roof block up or crack, water runs into the cabin, the carpet soaks through, and the electronics in the floor get wet too. It shows up on cars built between 2019 and 2021. A car without a roof is not affected, but a listing does not always say whether a roof was fitted, so you have to look.

In the EA211 the water pump and the thermostat are one plastic module, and the pump is driven not by the timing belt but by a separate toothed belt behind the exhaust camshaft. There are usually two problems with it: the plastic housing warps or cracks (slow coolant loss, a sweet smell, rising temperature), or the drive belt ages (a chirping noise, then an engine left with no cooling). The housing is particularly sensitive if oil reaches it: for example from a leaking crankcase ventilation. The module has to be replaced whole: dismantling it warps it in itself.

At low revs, mostly when cold and in the lower gears, the engine jerks; in extreme cases it stalls in a roundabout or at a junction. The cause of the phenomenon is the lean mixture used to heat the catalytic converter quickly, so it is software in origin. The maker released an update in March 2020, whose effectiveness owners judge differently.

The most common complaint on the Q3 is the infotainment system: the touchscreen does not respond, dash warnings flicker, the system freezes, or a sensor is faulty. One survey found a fault of this kind on 44 per cent of Q3 cars, and half of the repairs spent more than a week in the workshop. A software update fixes many cases and the update is free, so before you buy, ask whether the latest version is installed.

The per cylinder ignition coil of these direct injection, turbocharged petrol engines fails. According to the Haynes service material this and similar simple electrical faults account for roughly eighty per cent of workshop visits.