What Does P0121 Mean on a 2024 Kia Sportage?
A P0121 code on your 2024 Kia Sportage points our diagnostic investigators to the throttle position sensor (TPS). The sensor is communicating within the expected voltage range but with an abnormal performance pattern—the ECM detects readings inconsistent with pedal input, airflow, and engine load calculations.
The 2024 Sportage—the fifth generation—offers the 2.5L MPI four-cylinder (187 hp), 1.6L Turbo GDI hybrid (227 hp combined), or 1.6L Turbo GDI PHEV (261 hp combined). The MPI engine's port injection provides the best throttle body cleanliness, while the GDI powertrains are more carbon-susceptible. All use electronic throttle control with an integrated TPS.
Common Symptoms to Watch For
- Check engine light on
- Hesitation during acceleration
- Rough or unstable idle
- 8-speed automatic or hybrid transmission feels off
- AWD response unpredictable
- Highway Driving Assist may behave erratically
Top Causes Ranked by Likelihood
- ECM software calibration (35%) – Calibration refinements for current-year vehicles. Cost: $0 under warranty.
- Throttle body manufacturing defect (30%) – Factory defect. Cost: $0 under warranty.
- Wiring or connector defect (20%) – Assembly variability. Cost: $0 under warranty.
- Carbon buildup (10%) – Unlikely at low mileage; MPI least susceptible. Cost: $120–$275 if not covered.
- Boost or intake leak (5%) – Factory issue on turbo models. Cost: $0 under warranty.
How Serious Is This Code?
P0121 is medium severity. Your Sportage is drivable but may feel sluggish. Kia's warranty makes this a free fix. Address it soon.
Diagnostic Path
Take your 2024 Sportage to a Kia dealer. KDS diagnostics, TSB checks, and all repairs are covered under warranty.
Can You Fix This Yourself?
Kia's 5yr/60k basic + 10yr/100k powertrain (original owner) covers everything. Dealer visit is free—use it.
Get a Free AI Diagnosis
MPI, hybrid, or PHEV? AutoDetective's free AI diagnosis gives you a powertrain-specific preliminary analysis before your dealer appointment.