The turbo four that powered a generation of Audis through the late 1990s and 2000s — old enough now that every common failure point is thoroughly documented, which works in a used buyer's favour.
This engine's reputation among independent specialists is strong precisely because it's been in service long enough for every weak point to be identified, documented, and in most cases, already fixed on surviving examples. The core bottom end is genuinely tough. What fails is ancillary: coil packs, PCV system components, and on earlier versions, the turbo's oil feed under neglect.
Not a guarantee, but a pattern seen consistently across owner forums and independent-garage reporting.
First coil pack failures; PCV system often needs attention around the same stage.
Timing belt and water pump replacement — non-negotiable, regardless of how the engine sounds or runs.
On a well-documented, belt-maintained example, the bottom end is typically still original and sound.
This is the single most important check on any EA113: get documented proof of the last timing belt replacement, and if there's any doubt, budget for doing it immediately regardless of what the seller claims.
A rough idle that clears above idle speed is a classic coil pack symptom — cheap to fix, but worth factoring into your offer.
Ask about oil change frequency specifically — this engine's turbo is more dependent on clean oil than most modern equivalents.
Model-specific pages, with notes on how it behaves in that particular car.