Hyundai T-GDi (badge, not an engine)

T-GDi is a badge, not an engine — turbocharged gasoline direct injection, which describes a fuel system rather than a design.

Our rows show it on 1.0 to 3.3 litres across Hyundai and Kia, covering the Kappa, Gamma, Theta, Smartstream and Lambda families — three-cylinder to V6. A 1.0 Kappa and a 3.3 Lambda share the badge and nothing else.

Establish the family, which is what this catalogue files these engines under and what every technical source uses.

⚑ What the badge does mean is direct injection with no port injector on most of them, and the consequence is the same as on every engine in that position: there is no petrol washing the back of the inlet valve, so oil mist from the crankcase breather bakes on and stays. Inlet-valve carbon is therefore a maintenance item rather than a fault — rough running at idle and light load, at high mileage, on an engine that is otherwise sound. It is cleaned, not repaired.

The Smartstream generation added port injection alongside precisely to solve this, so the family and the model year decide whether the problem applies at all.