2020 Buick Enclave Fuel system Problems

My car started making a loud and rattling noise and when I had my vehicle looked at there was a huge crack in my exhaust pipe which could potentially be leaking harmful toxins in the cabin of my vehicle. I have been to so many places who say they don’t have what they need to repair this and that I need to reach out to GM. I have seen over 30 similar stories in these complaints. This is very unsafe and something needs to be done about this for the 2020 model as it has been done for others. We are afraid to even keep all the windows rolled up with our children inside for fear of carbon monoxide leaking through.

NHTSA ID

11766314

Incident

Aug 26, 2026

The vehicle developed an exhaust leak caused by both weld points on the front exhaust pipe breaking. A dealership inspected the vehicle and confirmed that the exhaust welds had failed, creating a hole in the exhaust pipe and triggering a P0420 catalyst efficiency code. The failure occurred at approximately 31,500 miles. The exhaust leak caused increased exhaust noise and emissions warning codes. The dealership recommended replacement of the front exhaust pipe assembly. This appears similar to known failures on the Buick Enclave and Chevrolet Traverse platform where the front exhaust pipe mounting bracket separates from the pipe due to weld failure. GM has issued special coverage adjustments for similar exhaust pipe bracket weld failures on other model years of these vehicles. The failure occurred at relatively low mileage and appears to be a structural weld defect in the exhaust system.

NHTSA ID

11724643

Incident

Mar 12, 2026

Dear NHTSA Safety Team, I am submitting a formal safety complaint regarding my 2020 Buick Enclave (VIN: [XXX] ). My vehicle has experienced repeated engine shutdowns while driving, creating a serious safety hazard. Vehicle & Incident Details: * Make/Model/Year: 2020 Buick Enclave * VIN: [XXX] * Mileage: ~116,834 miles (purchased at ~62,000 miles, used) * Purchase Date: [Insert Month/Year] * Dealer: Kyle Durrence Claxton Dealership Repair History: * First repair attempt: TPMS system * Second repair attempt: Connector assembly block * Total out-of-pocket spent: $4,000+ * Despite these repairs, the vehicle continues to shut off unexpectedly while driving. Safety Impact: * Engine shuts off while the vehicle is in motion, creating a risk of collision. * Vehicle is my only mode of transportation. * Dealership has not provided a loaner vehicle. Additional Concerns: * I have discovered forged signatures on my original finance/loan paperwork from the dealership, which I previously reported to the dealership General Manager without response. Requested Action: I request that NHTSA record this safety issue, investigate the repeated engine shutdowns, and consider whether this defect warrants a recall or further manufacturer action. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11719053

Incident

Feb 19, 2026

The contact owns a 2020 Buick Enclave. The contact stated that the check engine warning light was illuminated. The vehicle was taken to an independent mechanic, where the evaporative emission system, vapor canister purge solenoid, and the control solenoid were replaced; however, the failure persisted. The contact stated that the vehicle was difficult to start, and the instrument cluster gauges were fluctuating. The contact stated that the failure had occurred after refueling the vehicle. The contact stated that the failure had progressively worsened. The vehicle was taken back to the independent mechanic, where it was determined that the failure was related to NHTSA Campaign Number: 20V639000 (Fuel System, Gasoline), and the contact was referred to the dealer for assistance. The vehicle was taken to the dealer to be diagnosed. The vehicle was not yet diagnosed or repaired. The manufacturer was notified of the failure and referred the contact to the NHTSA Hotline for assistance. The failure mileage was approximately 42,000.

NHTSA ID

11673314

Incident

Jan 1, 2025

Mileage

42,000 mi

Welds have broken loose from exhaust creating a hole and loud noise & strong exhaust smell

NHTSA ID

11640093

Incident

Jan 28, 2025

Vehicle would not go into park fortunately we were in a safe location to avoid a possible accident or injury. The vehicle has electronic transmission shifting. According to the dealership the park solenoid in the transmission valve body failed. This prevented us from putting the vehicle in park so it could safely be shut off. We were able to set electronic parking brake but ignition continued to remain on. Eventually had to disconnect the negative battery terminal. Had vehicle towed to dealership but could not release electric park bake or start vehicle with battery terminal reconnected. This is becoming a common problem with this transmission, so common that parts are on back order. This could be a very unsafe problem with this vehicle in the right circumstance. There should be a recall on this transmit that is used on multiple GM vehicles

NHTSA ID

11610097

Incident

Aug 20, 2024

After filling up fuel, vehicle runs rough, hesitates, and stalls at idle speeds. This occurs after every fill up. The check engine light comes on and states an issue with the anti-lock brake system. I’ve had the vehicle checked by Buick 5 times and they have not been able to replicate the issue, so troubleshooting stopped. I know a recall came out this July for 2019 Buick Enclaves to replace the evaporative emissions purge valve due to not fully closing. This is the issue with my 2020 Buick Enclave and is a massive safety concern as the vehicle stalls while driving at slow speeds after fill up. Most recent event occurred on October 5th. I’ve posted a picture from last year that captured the same issue.

NHTSA ID

11548946

Incident

Oct 5, 2023

TL* THE CONTACT OWNS A 2020 BUICK ENCLAVE. THE CONTACT STATED THAT WHILE DRIVING DOWNHILL AT APPROXIMATELY 75 MPH, THE VEHICLE DECELERATED TO APPROXIMATELY 20 MPH WITH 'CAN NOT SHIFT IN THIS POSITION' MESSAGE DISPLAYED ON THE INSTRUMENT PANEL. THE VEHICLE WAS TOWED TO SOMERSET BUICK LOCATED AT 1850 W. MAPLE RD, TROY, MI 48084, WHO DIAGNOSED THAT THE FUEL TANK SENSOR WAS FAULTY. THE FUEL TANK SENSOR WAS REPLACED HOWEVER, THE FAILURE RECURRED. THE TRANSMISSION SERVICE REQUIRED MESSAGE WAS DISPLAYED ON THE INSTRUMENT PANEL. THE CAUSE OF THE FAILURE WAS NOT YET DETERMINED. THE MANUFACTURER WAS NOTIFIED OF THE FAILURE. THE APPROXIMATE FAILURE MILEAGE WAS 7,100.

NHTSA ID

11415777

Incident

Apr 2, 2021

Mileage

7,100 mi