2020 Hyundai Sonata fuel/propulsion system problems

“The car has strong fuel smell in the cabin when tank is full, It is especially strong after car sits. I have taken to hyundai several times for this problem. They say the computer says nothing is wrong. They refuse to investigate as they dont smell the odor.”

“Vehicle experienced intermittent, severe powertrain defect resulting in a critical safety hazard. Between 30K and 36K miles, the vehicle underwent 3 violent highway deceleration episodes. During these events, the engine began shaking, escalating to violent shaking; with deceleration and coming to a stop, it would shake, then sputter as if it would die. Coming to a complete stop, a total stall was prevented only by the ECM forcing a limp mode lock at 1200 RPMs. When Auto Hold was engaged at this point and my foot was removed from the brake pedal, the mechanical surge caused the vehicle to unexpectedly lurch forward, fighting against and nearly overriding the factory Auto Hold braking safety feature before finally holding. Luckily, no pedestrian was walking in front of my car when this occurred. No check engine light (CEL) or dashboard warning ever illuminated. This safety compromise is directly tied to an ineffective or adjacent remedy involving Service Campaign 9B1 (Opcode 40D219R0) and Safety Recall 286. Under this Opcode, a factory software flash deleted the standard OBD-II trouble code P0451and substituted it with a manufacturer-specific shadow code P14EE00.…”

“Car was taken to dealership for inspection. Upon inspection, it was determined that the fuel tank had expanded and pushed towards the heat shield, and expanded upward pushing up the back seats of vehicle. It was determined to not safe to drive. Manufacturer contacted me and offered a buyback. Upon their offer of a buyback, it was determined that I would owe the manufacturer approximately $2,000. I have requested that they fix it, and they have refused to give me the paperwork I requested about the car's condition and fixability. I am in the process of negotiating and am filing this complaint for the record.”

“Hyundai Motors America has failed to comply with its statutory obligations in conducting the recall campaign 25V796, and is instead engaging in behavior substantially similar to that which has been previously censured by NHTSA. My Sonata suffered irreparable damage related to this campaign as confirmed by HMA. 49 U.S.C. § 30120(a)(1)(A) allows HMA to choose one of three remedies: repair, replacement, or refund. However, they 1) say it cannot be safely repaired, 2) will not replace it, and 3) are not offering a repurchase as required by statute, i.e. "by refunding the purchase price, less a reasonable allowance for depreciation." Instead, Hyundai's case manager Aditya informed me on 5/29/2026 at 12:57 PM that they will make a repurchase offer "based on the Kelly Blue Book value." I protested and cited the statute, but he maintained that Hyundai has their process and subsequently gave an unconscionably low offer that was not based on any reasonable measure of depreciation. I insisted on a reasonable, defensible calculation. I proposed 1) using the state formula for calculating reasonable depreciation as applied in both Texas and California (HMA and my home…”

“NHTSA Complaint Statement Subject: Stop‑Drive Recall – Vehicle Held Since March 5, 2026 – No Remedy, No Transportation, Buyback Delayed I am filing a complaint regarding a stop‑drive safety recall that has left me without access to my vehicle since March 5, 2026, and the manufacturer has not provided a timely remedy, transportation assistance, or a completed buyback. My vehicle has been at the dealership since March 5 due to a manufacturer-issued stop‑drive recall. The dealership has confirmed they cannot legally release the vehicle because of the stop‑drive order. The vehicle is not repairable at this time, and the manufacturer initiated a buyback process. However, the manufacturer has been extremely slow to communicate or complete the buyback. Despite multiple attempts to contact them, I have not received a clear timeline, and the process has stalled. I have also not been provided with a loaner vehicle or consistent rental reimbursement, even though the stop‑drive order prevents me from using my car. Because of the delay, I am now facing financial hardship, including a past‑due car loan on a vehicle I cannot legally drive and cannot retrieve. I am effectively…”

“Vehicle subject to NHTSA Recall 25V796000 (fuel system defect). In July 2025, while driving, a loud explosive sound came from the rear of the vehicle followed by raw gasoline fumes entering the cabin. Vehicle was towed to a Hyundai dealership and held approximately 120 days before being returned as repaired. In December 2025, the exact same defect recurred. A third-party diagnostic scan (performed before drop-off) confirmed DTC Code P14EE — Fuel Tank Check Valve / Evaporative Purge System failure — directly related to the recall. The vehicle was held an additional 110+ days while the dealer awaited a new remedy from the manufacturer. Total days out of service: 230+. The recall repair has now failed twice. The safety defect was never successfully corrected after a reasonable number of attempts. The vehicle is currently being withheld by the dealership pending an unrelated disputed repair charge.”