What Does P0121 Mean on a 2022 Kia K5?
A P0121 code on your 2022 Kia K5 means the throttle position sensor (TPS) is communicating within the expected voltage range but with an abnormal signal pattern. The ECM detects data that doesn't match its calculations from pedal input, airflow, and engine load parameters.
Your 2022 K5 offers the 2.5L MPI (191 hp), 1.6L Turbo GDI (180 hp), or 2.5L Turbo GDI (290 hp in the GT). MPI keeps the throttle body clean; GDI engines are more carbon-prone. All pair with an 8-speed automatic or DCT.
Common Symptoms to Watch For
- Check engine light on
- Hesitation during acceleration
- Rough or hunting idle
- Transmission shifts feel off
- Throttle response inconsistent between modes
- Reduced fuel economy
Top Causes Ranked by Likelihood
- Carbon buildup on throttle body (30%) – At 2-4 years, early deposits on GDI engines. MPI least affected. Cost: $120–$250.
- Throttle body assembly failure (25%) – Internal TPS defect. Cost: $0 under warranty; $250–$480 otherwise.
- ECM software calibration (25%) – An available update. Cost: $0 under warranty.
- Wiring or connector issue (15%) – Corrosion or assembly variability. Cost: $0 under warranty.
- Intake system leak (5%) – Gasket or boot issue. Cost: $0 under warranty.
How Serious Is This Code?
P0121 is medium severity. Address this soon—warranty makes it easy.
Diagnostic Path
Your 2022 K5 is under Kia's warranty. Dealer KDS diagnostics are free and efficient.
Can You Fix This Yourself?
Kia's 5yr/60k basic warranty covers your 2022 K5. Original owners get 10yr/100k powertrain. Use your warranty.
Get a Free AI Diagnosis
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