Buick Encore GX loss of power problems

Filed Nov 8, 2026 · Acceleration, Electrical · MI

Battery all of sudden will not start. New transmission at 55,000 miles Reduced power Ecs light on

Filed Oct 22, 2026 · Electrical, Engine · MA

I am reporting a recurring safety issue involving unexpected stalling and loss of propulsion in a 2022 Buick Encore GX. In February 2026, the dealership replaced the vehicle's transmission with a rebuilt transmission. Since then, the vehicle has continued to experience sporadic stalling and drivability failures over the past eight months. It has been brought to the dealership at least six times since February for inspection and repair. Despite these efforts, the problem continues. Most recently, on October 20, 2026, the vehicle unexpectedly stalled while my husband was driving in downtown Boston. It had to be towed to an impound facility and, after retrieval, was towed to the dealership, where it currently remains available for inspection. There were no symptoms and no warning lights prior to the incident outside of the months of similar sporadic incidents. The vehicle has spent more than 25 business days at the dealership since February. Despite the rebuilt transmission replacement and repeated repair attempts, the stalling issue remains unresolved. It goes without saying that unexpected stalling and loss of propulsion pose a serious safety risk, particularly in congested city traffic and on busy roadways. Sudden loss of power can leave the vehicle stranded in traffic, prevent safe maneuvering, and increase the risk of a collision. The dealership has repeatedly inspected and attempted to repair the vehicle, including replacing the transmission, but the problem continues. I have also submitted a complaint with GMC. I request that the federal safety agency investigate whether this recurring failure represents a safety-related defect affecting this vehicle or other vehicles of the same make and model.

Filed Sep 26, 2026 · Acceleration, Electrical · KS

While driving my 2020 Buick Encore GX, the vehicle experienced a sudden and dangerous loss of acceleration, immediately dropping into 'Reduced Engine power' limp mode in active traffic, but no other car was Infront or behind my car. A diagnostic scan revealed Diagnostic Trouble Code (DTC) P2138, which triggered the computer's safety override system to cut engine throttle. The official dealer repair invoice confirms a manufacturing and assembly defect covered under GM Technical Service Bulletin (TSB) #07-06-04-019G. The technician located water intrusion Panel/Body Harness Connector X112. The root cause was an improperly seated weather seal from the factory, which allowed moisture to short-circuit the accelerator pedal sensor voltage lines. The shop had to reposition the factory seal and apply dielectric grease to the terminals to correct the defect, for which I was charged out of pocket. This manufacturing defect caused a sudden, unpredictable loss of vehicle power on public roads, creating a severe rear-end collision hazard.

Filed Aug 5, 2026 · NC

I was driving in heavy traffic when I got a reduced power message. There was no where for me to go to get out of the traffic. This is the second time I've had this issue. I have already replaced the entire turbo several months ago. I took it to the dealer then. They attempted to fix it with just replacing part of it. It didn't fix. The cost to fix it at the dealer was more than I could afford so I took it to a different shop. All together it cost around $2000. Now it's happening again!!

Filed Jul 8, 2026 · Electrical, Engine · NJ

While driving check engine suddenly illuminated following by a "warning reduced engine power" message. Car began driving sluggish and driving over 35mph caused serious trembling. After multiple diagnosis with several engine codes pointing to issues with ECM, and mass air flow sensor, and the wiring affliated . I took the vehicle to the GMC dealership to get vehicle serviced and was told the wiring had broken and melted which caused the check engine to come on and the vehicle to drive the way it did. The cause was the zip tie being tied too tight as stated in GMs own bulletin number 22-NA-008. This should be a bulletin it should be a recall!

Filed Apr 23, 2026 · Acceleration, Engine · OH

Turbocharger is defective. Reduced engine power. Engine Power reduced shows up on my dashboard. I bought the car brand new at Lindsey Buick in Ohio. This car is too young for this problem. Lindsey Buick and GM need to stand up to accountability and transparency when it comes to delivering top quality products. My vehicle almost caused a horrific accident by not accelerating fast enough. I am [XXX] , a widow, and in need of my car being fixed. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Apr 1, 2026 · Engine, Transmission · CO

Second complete powertrain failure on March 14, 2026 at 13,993 miles, nine days after first repair (complete transmission replacement for bone-dry sealed transmission). Symptoms: sudden loss of power on highway (unable to exceed 20 mph with accelerator fully depressed), hollow sound, noise described as "like a rock tumbling around inside." OnStar diagnostics returned "No Error Code Found" twice (11:14 AM and 11:17 AM) during active failure. Dealer (Loveland Buick GMC) diagnosed "battery issue" but provided indefinite loaner with no return date. Symptoms are consistent with engine bearing or connecting rod failure matching Cook et al. v. General Motors (Case No. 1:26-cv-00229, D. Del., filed March 4, 2026) covering 1.2L/1.3L turbo engines in the Buick Encore platform. Complaint alleges GM knew about defect "since 2022, if not earlier" and instructed dealers to tell consumers vehicles are "operating normally." First failure involved sealed transmission running with zero fluid. Skipped oil change after transmission repair (documented in GM Executive Resolution emails) may have allowed metal contamination to damage engine components. Requesting investigation into whether dealer's "battery" diagnosis was accurate or whether actual diagnostic codes indicate engine failure consistent with Cook v. GM class pattern.

Filed Apr 1, 2026 · Transmission · CO

Sealed transmission found "bone dry" at approximately 13,000 miles. No consumer-accessible dipstick. Complete transmission failure January 2, 2026. Second complete powertrain failure March 14, 2026, nine days after first repair completed. Symptoms on second failure (loss of power, hollow tumbling sound) consistent with engine bearing/connecting rod failure matching Cook et al. v. General Motors (Case No. 1:26-cv-00229, D. Del.) covering 1.2L/1.3L turbo engines. Dealer diagnosed "battery issue" on second failure and provided indefinite loaner. Vehicle purchased June 2025. Two failures within 9 months and 13,000 miles on a sealed powertrain system the consumer cannot inspect.

Filed Feb 17, 2026 · Engine, Transmission · TX

2020 Buick Encore GX; pulling out of a service station, my check engine light illuminated, and message on cluster stated: Engine Power Reduced. I loss throttle response for accelerating. Accelerator pedal was pushed to the floor and no acceleration. Vehicle entered limp mode. Drove 15 miles from service station to my home, in limp mode, unable to accelerate. Called a technician mechanic who check for Diagnostic Trouble Codes; DTC P0299 Turbocharge/Supercharge "A" Under boost condition; is Confirmed, Pending, and Permanent code. Loss of power to Power Train, unable to accelerate.

Filed Jan 5, 2026 · Engine, Fuel system · AL

Trying to understand why a recall was not done on an engine issue on this car and instead GMC chose to send out 2 letters in 2024 detailing the problem that "might" happen with the engine losing power while driving and for owners to "carry" the letters in the glove compartment of the vehicle so the dealership could be aware of the issue. You were told to not bring the car to be serviced unless the issue was obvious. Well it happened when I was out of state and had to immediately find a GMC dealership to fix the issue for which my car was in a dealership in [XXX] for approximately one month. If the proper recall would have been made I would NOT have driven the car out of state prior to getting it fixed. I had family members in the car with me at the time and to lose power on an interstate was very scary to say the least. I feel that GMC failed it's customers with this vehicle and I will never buy another GMC vehicle or for that another vehicle US made vehicle. The issue was fixed at GMC's expense but they are now failing to reimburse proper funds for the rental I had to use putting a burden on my finances...be that as it may I am totally disappointed with the Buick Encore GX 2021. You try to support the "american made label" and this is where it got me for trying to do the right thing...I feel no one is looking out for the consumers on this particular issue b/c I'm pretty sure I'm not the only one it has happened to...A RECALL SHOULD HAVE BEEN DONE ON THIS ISSUE..!! This is 2021 with fewer than 48,000 miles and up to date services by reputable GMC dealerships since I have had the car. The case # with GMC for this issue is XXXINFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)