2021 Kia K5 fuel system problems

Filed Nov 5, 2026 · Fuel system · 91,435 miles · SC

The contact owns a 2021 Kia K5. The contact stated that while her husband was entering the vehicle, the rear seat was elevated. The contact stated that upon inspection, it was discovered that the fuel tank had abnormally expanded. The vehicle was taken to the dealer, and the contact was informed that the vehicle was unrepairable. The contact received notification of the federal safety agency Campaign Number: 25V794000 (Fuel System, Gasoline). The Kia Customer Care was contacted by phone and a case was opened; however, no further updates were provided. A loaner vehicle was provided. The failure mileage was approximately 91,435.

Filed Nov 1, 2026 · Fuel system · TX

I am reporting a potential safety defect involving the fuel tank system of my 2021 Kia K5 LS. On August 17, 2026, my vehicle was inspected at Bayway Kia in connection with Kia recall SC356. The dealership documented the following on Repair Order #4972: "Recall SC356. Check and found fuel tank fail. Then open a Techline case." The dealership's documentation indicates that a fuel tank failure was identified and a Techline case was opened with Kia for further review. Kia America subsequently informed me that its preliminary evaluation found that the rear seat pan and strap deformation were consistent with the fuel tank expansion condition. I was advised that the vehicle was unsafe to drive. No repair addressing the documented fuel tank failure has been performed. The exact component failure and its cause have not been explained to me. Despite repeated requests, I have not received the detailed diagnostic findings, technician notes, photographs, diagnostic codes, or complete Techline case documentation. I am concerned about the potential safety implications of a fuel tank failure and the reported deformation of the surrounding vehicle structure, including whether the condition could create a risk of fuel leakage or fire. I am not claiming that a leak or fire occurred; I am requesting an independent safety review. The vehicle was inspected by Bayway Kia, and Kia America conducted a preliminary evaluation. The vehicle's availability for further inspection can be confirmed with the dealership. I do not know whether any warning lights or symptoms appeared before the inspection. I am requesting that the federal safety agency review this documented fuel tank failure, the associated deformation, and whether this condition may present a safety risk to occupants or other motorists.

Filed Oct 9, 2026 · Brakes, Engine · KS

I am filing a safety complaint regarding my Kia K5 because I am concerned about a potentially dangerous mechanical defect. I purchased this vehicle used from CarMax approximately two years ago. Within the first 30 days of ownership, the steering wheel began shaking. CarMax repaired the problem at no cost after ordering a replacement part. Approximately two weeks ago, the steering wheel began shaking again. The problem has now progressed to the vehicle shaking, feeling as though it is skidding or slipping, and failing to accelerate properly. The check-engine light is illuminated. I contacted Kia regarding recall SC250 and was told that my vehicle does not qualify. I am concerned because my vehicle is now experiencing symptoms that I believe warrant investigation into whether they could be related to the defect addressed by this recall. I am requesting that the federal safety agency investigate whether my vehicle may have an unresolved or related safety defect, and whether other vehicles excluded from the recall could be experiencing similar problems. I am concerned about the risk of losing acceleration while driving, potentially putting me and other motorists in danger. I can provide my VIN, vehicle mileage, repair history from CarMax, and any diagnostic information available.

Filed Sep 21, 2026 · Body, Fuel system · TX

2021 Kia K5 99K1ZRECALL Gas tank expanded and deformed the body, noticeable under back seat. Risk of gas leak or fire Kia of Mckinney service center has vehicle unrepairable SC356 KIA has case # 26282908 No symptoms, driver complained stopping was jerky CAN'T FIX CAR AND WON'T REPLACE IT.

Filed Sep 16, 2026 · Engine, Fuel system · CA

Vehicle experienced a severe engine misfire (P0302), rough running, and loss of power while driving. Dealership confirmed the Purge Control / PCV valve failed (replaced under Recall SC356 / 25V‑794), but charged out-of-pocket for the Cylinder 2 ignition coil that failed as a direct result of the PCV valve failure. The Dealership replaced the Purge Control/PCV valve at this time - the recall was not resolved until this time - I wasn't even aware of this recall until this incident. This ocurred on XXX and as a result I was stranded 1500 miles from home in [XXX] (I live in [XXX] and was driving the vehicle to my son at the University of XXX in [XXX]. The car was running fine until I stopped briefly in [XXX] and when I started the car, the engine light came on and the car's engine started sputtering and losing power as I was driving. Due to the fact that I was not in the vicinity of any Kia Dealerships or any open mechanics as it was Labor Day, I somehow managed to drive the car all the way to [XXX] as this was the closest dealership (over 120 miles away from where I was when the engine light came on). Once I arrived in [XXX], I checked into a hotel. I then attempted to drive to the nearest Kia Dealership the following morning at approximately 6:45 am and the engine light started flashing. I knew that this meant I was not able to safely drive the car even the additional 5 miles to the dealership so I pulled over and called Kia Roadside assistance and the dealership. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Aug 17, 2026 · Fuel system · CA

I am reporting a violation of the National Traffic and Motor Vehicle Safety Act by Ball Kia (National City, CA). The dealer tried to deny service for recall 25V794000 (SC356) for a melted, leaking fuel tank, fabricated a false diagnostic narrative of road impact to exploit me, and tried to charge $3,000 out-of-pocket for a federally mandated free repair.My vehicle has a severe fuel leak from a compromised fuel tank. Ball Kia service refused the recall, claiming "external aesthetic factors" or "road debris impact" caused it, and pressured me to tow it away.Using my military infantry experience in mechanical damage assessment, I inspected the vehicle in the service bay. I verified there is absolutely no puncture, tear, scrape, or kinetic impact on the fuel tank assembly. The dealer pointed to a split in the fuel tank protector panel, but a professional assessment shows this is false. The plastic protector panel failed due to extreme thermal exposure; the expanding tank pressed it against the hot exhaust, causing it to melt and tear under heat/pressure, not a kinetic strike.The tank itself is structurally melted and deformed with zero signs of road impact. This physical evidence matches the exact defect mechanism in the federal safety agency recall: a deteriorated check valve allows intake pressure into the fuel tank, causing it to expand, hit hot exhaust components, melt, and leak.Only after I read the exact the federal safety agency safety risk and remedy text verbatim did the service manager back down and open a manufacturer Tech Line.Because I had to fight a fraudulent diagnosis to get this safety mandate acknowledged, I fear internal dealership retaliation, being blacklisted, or receiving a subpar, dangerous repair. Leaving a high-risk fire defect unaddressed is a public safety hazard. Please audit Ball Kia's handling of campaign 25V794000 to ensure they are not endangering or defrauding other affected Kia K5 owners.

Filed Aug 17, 2026 · Fuel system · 111,000 miles · GA

The contact owns a 2021 Kia K5. The contact received notification of the federal safety agency Campaign Number: 25V794000 (Fuel System, Gasoline). The vehicle was taken to a dealer for the recall repair. The contact was struggling to receive updates on the status of the vehicle. The contact spoke with a service clerk and was informed that the repair was going well and that only one recall test remained. However, a supervisor later called and stated that the recall repair could not be completed. The vehicle could not be repaired. The vehicle was no longer functional due to a high risk of catching fire from fuel tank swelling caused by the recall defect. The contact stated that prior to the dealer visit, the vehicle had no issues but became inoperable. The vehicle was not repaired, and the dealer stated that the vehicle could not be repaired. The manufacturer was made aware of the issue. The failure mileage was approximately 111,000.

Filed Jul 30, 2026 · Fuel system, Transmission · GA

Recall NNK post-repair failure. Dealership: Kia of Valdosta (RO# XXX). After ECU update NNK-02-0118, my K5 suffered a severe loss of acceleration and torque. The car cannot safely merge on highways. The dealer’s own live scan data sheet proves that at 4,997 RPM under full load, the Turbo Recirculation (Dump) Valve reads "OFF". The factory tool key explicitly states (OFF = Open). The service manager is misreading the tool, claiming "OFF" means closed, and refuses to fix it. The boost gauge only rises under heavy floor acceleration, proving an uncalibrated boost leak. I have uploaded a photo of the technician's data sheet directly to the attachments and will also drop link to videos of my car in normal and sport mode. I have also opened Kia Corporate Case #XXX. I demand a corporate Regional Technical Manager review this data and authorize a Turbocharger Recirculation Valve (RCV) and Wastegate Adaptation Relearn at an alternate dealer...... 1. [XXX] 2. [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Jul 23, 2026 · Engine, Fuel system · 119,185 miles · MD

The contact owns a 2021 Kia K5. The contact stated that while driving approximately 55 MPH, the fuel gauge suddenly went from one-half tank to empty. The fuel level displayed 120 miles to empty. The contact attempted to refuel the vehicle but was unable to add fuel to the tank. The contact also stated that the oil warning light and the TPMS warning light was illuminated. The contact associated the failure with the federal safety agency Campaign Number: 25V794000 (Fuel System, Gasoline). The local dealer was not contacted. The vehicle was not diagnosed or repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 119,185.

Filed Jul 22, 2026 · Engine, Fuel system · 120,000 miles · FL

The contact owns a 2021 Kia K5. The contact stated that there were failures with the spark plugs. While driving at an undisclosed speed, the vehicle shuddered, and the engine sputtered. The contact stated that fuel spewed out of the filler neck while refueling the vehicle, and the fuel gauge incorrectly indicated that the fuel tank was empty after refueling. Additionally, there was an abnormal egg and sulfur odor coming from the vehicle with the check engine warning light intermittently illuminated. The contact stated that the vehicle was taken to a local dealer and inspected under the federal safety agency Campaign Number: 25V794000 (Fuel System, Gasoline). During the inspection, the seats were damaged. The vehicle was not repaired. The manufacturer was notified of the failure and was negotiating a buyback. The failure mileage was approximately 120,000.