P2135 on Chevrolet
Throttle/Pedal Position Sensor Voltage Correlation
P2135 on Chevrolet vehicles indicates throttle/pedal position sensor voltage correlation. Au7o has documented this code across 6 Chevrolet models — most commonly on Avalanche, Camaro, Impala. P2135 means the powertrain computer detected that the two throttle position (TP) or accelerator pedal position sensors disagree with each other. Drive-by-wire systems use redundant sensors so the PCM can cross-check the throttle or pedal reading for safety; if the two signals don't correlate within an expected range, this code sets. As a fail-safe, the vehicle often enters a reduced-power 'limp' mode, causing sluggish acceleration, a stuck or hesitant throttle, and a warning light. Because it affects throttle control, it should be addressed promptly. Typical repair costs on Chevrolet range from $100 to $700, depending on the specific model and root cause.
Common Causes of P2135
- •Faulty throttle position sensor / throttle body assembly
- •Faulty accelerator pedal position sensor
- •Damaged wiring or connectors at the throttle body or pedal
- •Corroded or loose connector terminals
- •Poor ground or reference voltage problem
- •Carbon buildup binding the electronic throttle plate
- •Failed PCM (rare)
P2135 on Chevrolet by Model
Chevrolet Avalanche(1 issue)
- Reduced Engine Power Mode from Throttle Body and Pedal Sensor Faults2007-2013
The 2007-2013 Avalanche frequently enters "Reduced Engine Power" mode, severely limiting acceleration. The most common causes are the electronic throttle body wearing out or the accelerator pedal position sensor (APP sensor) developing faults. The vehicle becomes barely drivable in this mode, struggling to accelerate to highway speeds. The issue can occur intermittently before becoming permanent.
Chevrolet Camaro(1 issue)
- Reduced Engine Power / Limp Mode from Throttle Body (P2135) Failure2010-2020
A 'Reduced Engine Power' warning that drops the car into limp mode (capped RPM and speed) is a common Camaro complaint traced to the electronic throttle body. When the two internal throttle-position sensors disagree, the PCM sets P2135 and limits power as a safety measure. It can also present as rough/shaky idle, stalling at stops, and hesitation on tip-in. Cleaning does not fix a sensor fault; the internal TPS has failed.
Chevrolet Impala(1 issue)
- Reduced Engine Power / Service StabiliTrak from Throttle Body Failure2006-2016
Impalas frequently throw a cluster of warnings at once — 'Engine Power Reduced,' 'Service StabiliTrak,' and 'Service Traction Control' — that are usually one underlying drive-by-wire fault rather than three separate failures. The most common root cause is the electronic throttle body actuator (or the dual throttle-position sensors inside it) going out of range; the accelerator pedal position sensors can also disagree. Because the ECM cross-checks these dual sensors, any disagreement forces the car into limp-home mode with drastically reduced power. Carbon buildup on the throttle plate aggravates it, especially in cold weather.
Chevrolet Silverado 1500(1 issue)
- Service StabiliTrak / Service Traction Control / 'Reduced Engine Power' Cascade2014-2022
A widely reported Silverado 1500 complaint is a sudden cascade of dash messages — 'StabiliTrak disabled,' then 'Service StabiliTrak,' 'Service Traction Control,' and finally 'Engine Power Reduced' — sometimes with a stumble or stall and limited throttle response. The most common root causes are a faulty accelerator pedal position (APP) sensor or throttle body (electronic throttle), but it is also frequently traced to poor/corroded ground connections and chafed wiring under the driver's door sill or at the underseat/main harness connector. Because it can drop the truck into reduced-power limp mode at speed, owners treat it as urgent.
Chevrolet Suburban(1 issue)
- Reduced Engine Power / Throttle Body (TAC) Failure2003-2007
The electronic (drive-by-wire) throttle system triggers a 'Reduced Engine Power' / 'Engine Power Is Reduced' limp mode that sharply limits acceleration and speed - dangerous when it strikes in traffic. The cause is usually the throttle actuator control (TAC): worn internal throttle-body sensors/motor, or a broken/chafed wire in the harness a few inches from the throttle-body connector. Correlation codes P2135 and TAC-performance code P1516 are typical.
Chevrolet Tahoe(1 issue)
- 'Reduced Engine Power' Limp Mode - Electronic Throttle (TAC) System2000-2010
Tahoes with drive-by-wire throttle (APP pedal sensor + TAC module + electronic throttle body) commonly trigger a 'Reduced Engine Power' message and drop into limp mode with severely limited acceleration - a safety concern in traffic. On GMT800s the frequent culprits are a broken/chafed wire in the throttle-body harness (often the yellow wire), corroded engine grounds, or a dirty/sticking throttle body (P1516/P1515). GMT900s see similar throttle-actuator/APP faults (P2101/P2135/P0120 family).
Looking for P2135 on a different make?
View P2135 across all makes →Frequently Asked Questions
What does P2135 mean on Chevrolet?▼
P2135 stands for "Throttle/Pedal Position Sensor Voltage Correlation." P2135 means the powertrain computer detected that the two throttle position (TP) or accelerator pedal position sensors disagree with each other. Drive-by-wire systems use redundant sensors so the PCM can cross-check the throttle or pedal reading for safety; if the two signals don't correlate within an expected range, this code sets. As a fail-safe, the vehicle often enters a reduced-power 'limp' mode, causing sluggish acceleration, a stuck or hesitant throttle, and a warning light. Because it affects throttle control, it should be addressed promptly. On Chevrolet specifically, this code is documented across 6 models.
What causes P2135 on Chevrolet vehicles?▼
Common causes on Chevrolet: Faulty throttle position sensor / throttle body assembly, Faulty accelerator pedal position sensor, Damaged wiring or connectors at the throttle body or pedal, Corroded or loose connector terminals, Poor ground or reference voltage problem. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P2135 on a Chevrolet?▼
Repair costs on Chevrolet range from $100 to $700, depending on the specific model and root cause.
Which Chevrolet models have P2135 documented?▼
Au7o has documented P2135 on 6 Chevrolet models: Avalanche, Camaro, Impala, Silverado 1500, Suburban, Tahoe.