P0121 on Chevrolet Vehicles
The throttle position reading is electrically valid but doesn't agree with engine load, airflow or rpm. P0121 →
8Complaints mentioning the code
#1Rank among 6 brands
0.6%Share of Chevrolet DTC complaints
In NHTSA owner complaints we analyzed for Chevrolet, P0121 was mentioned 8 times.
Most mentioned models
| Chevrolet Traverse | 3 | |
|---|---|---|
| Chevrolet Impala | 2 | |
| Chevrolet Camaro | 1 | |
| Chevrolet Malibu Maxx | 1 | |
| Chevrolet Silverado | 1 |
Model years mentioned
Components named in these complaints
- Electrical System (5)
- Electronic Stability Control (esc) (3)
- Engine (3)
- Power Train (2)
- Vehicle Speed Control (2)
Reports with a crash: 1 · fire: 0 · injuries: 0
Often appears together with
P2176
Powertrain
The PCM hasn't stored where the closed throttle sits, usually after a battery disconnect…
Low
P0221
Powertrain
The second throttle angle signal leaves its window or stops following the plate, so power…
Moderate
P0171
Powertrain
The engine computer is adding the maximum extra fuel it's allowed on bank 1 and still sees…
Moderate
Possible causes
- TPS drifted or worn so its output no longer matches actual throttle angle
- Intake air leak after the throttle (cracked hose, PCV, gasket) making load high at a small throttle angle
- MAF or MAP sensor reporting wrong airflow, so the comparison fails
- Throttle plate not closing to its learned position: heavy carbon, tampered idle stop screw or sticking cable
Related codes
Source: NHTSA Complaints API (US government open data), analyzed by DTC mention.