What Does P0121 Mean on a 2023 Kia Telluride?
P0121 on your 2023 Kia Telluride means the throttle position sensor (TPS) is transmitting voltage within normal range but with an abnormal pattern. The ECM detects a mismatch between TPS data and its calculations from pedal input, airflow, and engine load.
The 2023 Telluride received a mid-cycle refresh with updated styling and the 3.8L Lambda II V6 (291 hp) continuing with an 8-speed automatic. Port injection keeps the throttle body naturally clean. As a refreshed model, calibration updates are relevant.
Common Symptoms to Watch For
- Check engine light on
- Hesitation during acceleration
- Rough idle
- 8-speed shifting feels off
- AWD response unpredictable
- Highway Driving Assist may disengage
Top Causes Ranked by Likelihood
- ECM software calibration (35%) – Refreshed models often receive software updates. Cost: $0 under warranty.
- Throttle body assembly defect (25%) – Factory quality issue. Cost: $0 under warranty.
- Wiring or connector issue (20%) – Assembly variability. Cost: $0 under warranty.
- Carbon buildup (15%) – At 1-3 years with port injection, unlikely but possible. Cost: $150–$300.
- Intake system leak (5%) – Gasket or vacuum issue. Cost: $0 under warranty.
How Serious Is This Code?
P0121 is medium severity. Warranty covers everything. Address this soon.
Diagnostic Path
Dealer KDS diagnostics—free under warranty.
Can You Fix This Yourself?
Full Kia warranty: 5yr/60k basic + 10yr/100k powertrain. Dealer visit is free.
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