P0121 on Your 2022 Genesis G70: The Case File
A P0121 on your 2022 Genesis G70 means the ECM has flagged an inconsistent throttle position sensor signal. The voltage is within range but the pattern doesn't match your accelerator input—our detective has identified a throttle body communication issue that needs investigation.
The 2022 G70 offers a 2.0L turbocharged four-cylinder (252 hp) or a 3.3L twin-turbo V6 (365 hp), both with direct injection and 8-speed automatic. The G70's sport sedan character demands precise throttle response. Both engines' DI fuel systems make them susceptible to carbon-related throttle issues.
Symptoms
- Check engine light on
- Hesitation during spirited acceleration
- Idle roughness
- Turbo response feels diminished
- Sport mode throttle feels inconsistent
Causes Ranked
- Carbon buildup on throttle body – Both DI engines accumulate carbon on the throttle plate. The 2.0T is more common, the 3.3T has a larger throttle body. Likelihood: 45%
- Throttle body assembly wear – Internal TPS or motor degradation. Likelihood: 25%
- ECM software update – Genesis/Hyundai releases calibration updates for the G70 platform. Likelihood: 15%
- Wiring or connector issue – Turbo engine bay heat effects. Likelihood: 10%
- Boost system interaction – Wastegate or piping issue. Likelihood: 5%
Repair Costs
- Throttle body cleaning: $100–$180 (shop) / $10–$25 (DIY)
- Throttle body replacement: $350–$600 parts and labor
- ECM update: $100–$200 (dealer)
- Wiring repair: $100–$250
Genesis Concierge Service
Your 2022 G70 should be within Genesis's 5-year/60,000-mile basic warranty and 10-year/100,000-mile powertrain warranty—the best in the luxury segment. Genesis offers Concierge valet service: they'll pick up your G70, leave a loaner, repair it, and bring it back. All P0121 repairs should be covered at no cost. The dealer uses Genesis GDS for diagnostics.
How AutoDetective AI Can Help
AutoDetective's AI differentiates between the G70's 2.0T and 3.3T engines. Upload your scan data for a free engine-specific diagnosis.