P2101 on Buick: How to Diagnose & Fix
Throttle Actuator "A" Control Motor Circuit Range/Performance
1 Buick model · 1 documented issue · $250-$600 repair
P2101 on Buick by model: symptoms, diagnosis and fix
A failing electronic throttle body or throttle position sensor triggers a 'Reduced Engine Power' message and limp mode, with rough or surging idle and hesitant acceleration. The condition is common enough that GM issued a special coverage adjustment extending the throttle body warranty on some 2009-2011 cars.
Common Symptoms
- 'Reduced Engine Power' message
- Limp mode / very limited acceleration
- Rough or surging idle, RPM jumping
- Hesitation on acceleration
- Check engine light
How to Fix
Clean the throttle body first; if the TPS/electronic throttle body has failed, replace it and perform the required throttle relearn so the computer sets correct idle and full-throttle positions. GM Special Coverage extended this to 10 years / 120,000 miles on covered 2009-2011 models.
Sources for this issue (1)
P2101 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P2101 mean on a Buick?
P2101 stands for "Throttle Actuator "A" Control Motor Circuit Range/Performance." This powertrain code means the engine computer commanded the electronic throttle actuator motor to a certain position but the motor did not respond within the expected range. Modern engines use a drive-by-wire throttle, where a motor opens and closes the throttle plate based on signals from the computer rather than a cable. When the actual throttle position disagrees with the commanded position, the computer sets this code, often forcing the vehicle into a reduced-power 'limp' mode to protect the engine. This can cause poor acceleration or stalling and should be addressed promptly. On Buick it is documented across 1 model: Lucerne.
What are the most common causes of P2101?
The most common causes of P2101 are: Faulty throttle actuator control motor (throttle body), Dirty or carbon-fouled throttle plate causing binding, Wiring or connector problems in the throttle actuator circuit, Failed throttle position sensor inside the throttle body, Poor electrical connection or corroded terminals, Faulty engine control module (less common). The specific cause varies by vehicle.
How much does it cost to fix P2101 on a Buick?
Published repair estimates on Buick range from $250 to $600 depending on the model and root cause. If an issue mentions a recall or campaign, check your VIN with the manufacturer or NHTSA and confirm eligibility and coverage with a dealer.
Looking for P2101 on a different make?
View P2101 across all makes →Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.