The B9-generation A4 with the EA888 Gen 3 petrol — a genuinely well-rounded saloon, with reliability that depends more on maintenance habits than on luck.
The B9 A4 is a lighter, more aerodynamically efficient platform than its predecessor, which takes real pressure off the 2.0 TFSI — this combination feels notably less strained than the same engine in heavier Q5 applications.
Quattro versions carry more driveline complexity (and more to go wrong long-term in the transfer case and rear differential), while front-wheel-drive versions are mechanically simpler and slightly cheaper to maintain.
This is about the car itself — for engine-specific failure points, see the dedicated engine page below.
This generation of A4 shares its 2.0 TFSI with the A3, A5, and Q5 of the same era. Full detail on carbon buildup, cooling system wear, and typical failure mileage lives on the dedicated engine page.
FULL ENGINE BREAKDOWNAudi 2.0 TFSI (EA888 Gen 3) — Reliable or Not →The B9 A4 was also offered with a diesel option — relevant if your use case leans toward long motorway commutes.
Ask for documented history of any carbon-cleaning service on the intake valves — not everyone does this preventatively, so proof of it is a genuine plus.
On Quattro versions, check for any noise or vibration from the rear differential area during a test drive, particularly at low speed on full lock.
Confirm the MMI infotainment system boots cleanly and the virtual cockpit display has no dead pixels or flicker — a known early-build complaint.