ENGINE · 2009-2015

G4KF tuning

G4KF — Hyundai/Kia 2.0 turbo Theta II (legacy). I4 turbo GDI Theta II, 2.0 L, 270-274 HP stock. Cars: Hyundai Sonata 2.0T (YF), Genesis Coupe 2.0T, Kia Optima 2.0T.

Engine specs

Engine codeG4KF
ConfigurationI4 turbo GDI Theta II
Displacement2.0 L
Production years2009-2015
Stock power270-274 HP
ECU familyContinental SIM2K-241 / Bosch MED17.9.8 →

Tuning stages on G4KF

Stage 1+30-50 HP
Stage 2+60-90 HP (intake + downpipe)
Stage 3+120+ HP (turbo upgrade)

Conservative real-world estimates. Actual results depend on hardware health, fuel quality, ambient temperature, and the specific calibration written.

Services available on G4KF

Common DTC codes on G4KF

Brands running G4KF

Workshop workflow

  1. Read the G4KF ECU via OBD or bench using your existing flasher (KESS3, AutoTuner, MPPS, Trasdata, FRF).
  2. Open Softechpro V5 and drag the .bin / .ori / .hex / .s19 / .frf onto the workspace. The Continental SIM2K-241 variant is auto-detected.
  3. Pick the service tab and apply Stage 1 / 2 / 3 / DPF OFF / EGR OFF / AdBlue OFF as required.
  4. Save patched .bin — the TPROT + multi-block CRC32 is recomputed automatically.
  5. Flash via your existing flasher. Adaptation reset via OEM scan tool if required.

Other Hyundai engines

Theta-IIR20G6DH / Lambda II 3.3T