2021 Kia K5 Fuel system Problems

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)

NHTSA ID

11753897

Incident

Jul 28, 2026

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 NHTSA 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.

NHTSA ID

11752335

Incident

Jul 22, 2026

Mileage

119,185 mi

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 NHTSA 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.

NHTSA ID

11752163

Incident

Feb 22, 2026

Mileage

120,000 mi

The contact owns a 2021 Kia K5. The contact received notification of NHTSA Campaign Number: 25V794000 (Fuel System, Gasoline); however, the part to do the recall repair was not yet available. The contact stated that while driving approximately 70 MPH, upon further inspection the fuel level was lowering unexpectedly. The check engine warning light was illuminated. The vehicle was taken to a local Auto Zone and was scanned with an OBD2 scanner and diagnosed with a recall-related failure. The vehicle was taken to a local dealer, where it was diagnosed with an expanded fuel tank; however, the vehicle was not repaired because the dealer was short-staffed. The dealer associated the failure with NHTSA Campaign Number: 25V794000 (Fuel System, Gasoline). The manufacturer was made aware of the failure; a case was filed; however, no assistance was provided. The failure mileage was approximately 90,000.

NHTSA ID

11751597

Incident

Jul 18, 2026

Mileage

90,000 mi

The contact owns a 2021 Kia K5. The contact stated that while driving approximately 55-60 MPH, the fuel tank expanded. There were no warning lights illuminated. The vehicle was towed to the local dealer, where it was determined that the fuel tank had expanded, and that the vehicle was unrepairable. The vehicle was not repaired. The dealer offered a buyback. The manufacturer was not contacted. The failure mileage was approximately 115,000.

NHTSA ID

11751470

Incident

Jul 8, 2026

Mileage

115,000 mi

My car is losing power upon acceleration causing a loss of power upon take off upon taking off and when gears are shifting. Told by dealer it is a problem with fuel injection. Replaced several coil packs and spark plugs on my own. Dealer repair shop had my car for 4 days for the fuel talk and valve issues and did not repair anything. Losing power when I drive in traffic and on highway is a huge safety issue causing loss of power when at highway speeds. I plugged in a code reader bought by myself which is telling me it’s coil packs. We have replaced several with no luck. There is a smell of fuel and with all the other fuel system recalls and after reading other complaints on this site that sounds similar, I fear this is a safety issue with the vehicle. They checked my fuel tank and valve but didn’t replace either. I believe this is related to all the other fuel system recalls and should be repaired free of charge by dealer as a dysfunctional fuel problem as nothing we’ve done to repair with the code reader has fixed this issue. I fear a loss of power of fire caused by the mounting fuel system issues of these issues have caused the issue I’m having. Please look into this as several other complaints I’ve read online by owners are having same issue. My car only has 68,000 miles. I’m in fear of serious injury as a cause of these issues. Also concerned dealer had my car 4 days and DID. NOT repair or replace fuel tank or fuel valve, why did they have my car this long and DID NOT REPAIR the recall that the vehicle was there and the appointment was scheduled for such? I really have a fear there is an accident in my vehicle travels caused by mounting fuel issue recalls and problems. Please please look into this and help with these mounting fuel system issues before serious injury or death!

NHTSA ID

11749168

Incident

Jun 5, 2026

I Heard a loud noise in the backseat twice and noticed the back seat raise up also the check engine light came on but also the fuel was going down and up (the gauge), is currently at the kia dealership and has been reported fail recall

NHTSA ID

11747487

Incident

Jun 29, 2026

I took my 2021 KIA K5 to the dealership in March of 2025 for an oil change. While I was there, a diagnostic test was conducted to determine if my vehicle was affected by a damaged check valve. Therefore, the car could have caught on fire while it was being driven. I was given a rental car while my vehicle was supposed to be fixed. KIA deemed my 2021 K5 to be a hazard to the road. In June of 2025, KIA offered to pay my loan balance off and give me less than $250 for the "down payment." Please note when I purchased the KIA K5 in 2021, I traded my 2018 KIA Optima. Now, in June of 2026, KIA in offering me $13,200 for my KIA K5. I have until June 29, 2026, to accept the offer. The balance on my loan will come out of that so, I will receive approximately $7000 for a car I will pay a total of $44,000 for. I never once stopped making my monthly payment and my car has been deemed a hazard for the road since March of 2025. For years, I drove a vehicle that could have potentially caused a death or injury.

NHTSA ID

11746075

Incident

Mar 28, 2025

The contact owns a 2021 Kia K5. The contact stated that there was an abnormal odor of fuel. The check engine light was illuminated. The contact received the recall notice for NHTSA Campaign Number: 25V794000 (Fuel System, Gasoline). An unknown local dealer was contacted, but the vehicle was not diagnosed or repaired. The manufacturer was contacted, but no assistance was provided. The failure mileage was approximately 200,000.

NHTSA ID

11737762

Incident

Mar 1, 2026

Mileage

200,000 mi

Manufacturer has failed to remedy the safety recall for my vehicle in a timely manner. Vehicle is a fire risk and I am unable to drive it. My vehicle has been sitting at the dealership service center for over a month. I have not been contacted by Kia as of yet even after repeated phone calls and emails for updates.

NHTSA ID

11734630

Incident

Mar 25, 2026

My vehicle is currently under a recall (recall SC356), but I'm currently very far from a Kia dealership. The nearest one is about 175 miles away. I contacted Kia and they informed me that they can't reimburse me for having my car towed to the dealership. So now I am stuck with a car that could possibly catch fire at anytime, according to the recall notice. And they refuse to help me.

NHTSA ID

11727249

Incident

Mar 26, 2026

The fuel tank malfunctioned while driving. It appeared on my odometer that I had zero gas, once I pulled into a gas station to fill up, I could see the gas pouring out of the tank while the pump was unable to pump any gas due to the pressure coming out of the tank. Bev Smith Kia of Fort Pierce has the vehicle if you would like to inspect it. I also have photos of the melted tank from the dealership. NHTSA Recall Number: 25V-794 The fuel tank expansion/melting risk, fuel leak, or fire risk, put the driver, passenger, and nearby citizens at risk if the car caught fire. Also, the seats have been known to eject with this particular recall. Yes the vehicle was inspected by Bev Smith Kia per my insistence, and instead of fixing it and returning the vehicle, Kia Corporate forced the hand of Bev Smith Kia to confiscate the vehicle due to it being a deadly recall. SC288 Alpha Campaign Failed is what the dealership told me to tell corporate. There were no warning lights when the odometer appeared to have zero miles, it simply went to zero and the backseat became very hot to the passenger. There was no ability to fill the gas tank as the pressure of gas was pouring gas out from the fuel tank and the pump would not add additional gas. This appeared in May of 2025. We took it to the dealership and they said there was nothing wrong with the car. The next time is happened was Sunday [XXX]. The car was taken to Bev Smith Kia dealership that Monday November 24th where it was confiscated by the dealership for the deadly recall that they claimed could never be fixed and Kia would do a buy back. There were no other issues with the vehicle prior to the incident in May of 2025. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11720975

Incident

Nov 24, 2025

The contact owns a 2021 Kia K5. The contact stated that while driving 65-70 MPH, the fuel gauge displayed zero miles to empty. The contact pulled into the nearest gas station, and while attempting to add fuel to the vehicle, the contact became aware that there was fuel leaking out of the fuel tank outlet, and the gas pump nozzle was stopped. The contact was unable to refuel the vehicle. The contact stated that after returning to drive, the fuel gauge indicated 100 miles to empty. The vehicle was taken to the dealer for the recall repair under NHTSA Campaign Number: 25V794000 (Fuel System, Gasoline), and the dealer advised the contact that the manufacturer had instructed the contact not release the vehicle to the owner due to the recall. While diagnosing the vehicle, a technician at the dealer sent a photo displaying that the rear driver's side seat had melted internally due to the fuel tank overheating. Additionally, the dealer informed the contact that the SC288 Alpha Campaign had failed. The vehicle remained at the dealer for four months; however, the manufacturer later sent a letter advising the contact that the vehicle could not be repaired, and a buyback was suggested. The manufacturer offered to reimburse the down payment for the vehicle. The contact stated that the buy-back offer was unsatisfactory. The contact declined the offer, and the manufacturer then threatened to tow the unrepaired vehicle back to the residence. The contact stated that the manufacturer had failed to honor the recall repair. The vehicle was not repaired. The failure mileage was approximately 145,000.

NHTSA ID

11720940

Incident

Nov 22, 2025

Mileage

145,000 mi

The contact owns a 2021 Kia K5. The contact stated that the check engine warning light remained illuminated with DTC: P0471 displayed. The vehicle was included in NHTSA Campaign Number: 25V794000 (Fuel System, Gasoline) and was taken to the dealer for the recall repair where the dealer replaced the check valve. After receiving the recall repair, the check engine warning light remained illuminated with DTC: P0471 displayed. The vehicle was returned to the dealer, who diagnosed that the Exhaust Pressure Sensor was causing the Exhaust Gas Recirculation (EGR) Sensor to fail and needed to be replaced. The vehicle had not been repaired. The manufacturer was made aware of the failure. The failure mileage was approximately 52,000.

NHTSA ID

11720629

Incident

Jan 29, 2026

Mileage

52,000 mi

Unknown

NHTSA ID

11719743

Incident

Feb 5, 2026

I originally got my car 2023 from Carmax I took it in to Kia dealership to get my recalls done they kept my car for over 6 days without fixing it when I arrived I was showed a photo saying it’s after market parts on this vehicle and we can’t touch it also they stated my vehicle was dangerous to drive so I asked for documentation that my vehicle was denied and they refused also I called Kia cooperate to file a complaint to get proper documentation that my vehicle was denied they told me it was denied as well and said they can’t give me paperwork to state anything

NHTSA ID

11718393

Incident

Jan 23, 2026

I brought my car in for the recall regarding the faulty check valve in the fuel tank. My check engine light had also just come on. I have a 2021 Kia K5 with 60,000 miles and the dealership tells me I have to replace all 4 fuel injectors since it's causing a "system too lean" message.

NHTSA ID

11713571

Incident

Jan 24, 2026

The contact owns a 2021 Kia K5. While driving at an undisclosed speed, the contact heard a loud explosion coming from the rear of the vehicle, and there was a dragging sound coming from the vehicle. The contact stated that the rear seat raised up into the air with children seated in the seat. The contact became aware of fuel leaking and that the fuel tank was hanging down. The vehicle was towed to the residence and was later driven to a KIA dealer. The manufacturer was made aware of the failure. The approximate failure mileage was 116,000.

NHTSA ID

11711403

Incident

Dec 8, 2025

Mileage

116,000 mi

The vehicle experiences severe stalling and loss of power while driving. When attempting to accelerate, the vehicle hesitates, shakes violently, and will not accelerate beyond approximately 10–20 mph. The vehicle then stalls completely and shuts off. These failures occur both after the vehicle has been parked and while actively driving. When placed in drive, the vehicle shakes aggressively and stalls. The check engine light is illuminated. The stalling has occurred multiple times in the middle of freeway traffic, creating an extreme safety hazard. My child has been in the vehicle during every occurrence. On one occasion, the vehicle shut off completely while on the freeway, placing our lives at risk and nearly resulting in a serious collision. This issue is unpredictable, persistent, and prevents safe operation of the vehicle. The vehicle has been inspected and worked on by Southwest Kia and A-Z Auto, but the defect continues to occur. I believe this is a manufacturing or design defect related to the engine or powertrain that poses a serious safety risk and should be investigated to determine whether other vehicles are affected.

NHTSA ID

11705473

Incident

Dec 16, 2025

Ever since I bought my car in July of 2025 cash I’ve been having issues. Shortly after purchasing my car began to stall , lose power repeatedly. I then took to southwest kia in Dallas they told me I had contaminated gas. They charged me $2,000 to clean my fuel lines , replace spark plugs & replace a fuel pressure sensor. Shortly after i got my car I had the same issues. I explained my concerns and they replaced my fuel tank free of charge. A week later same issue so I went to a local mechanic and he replaced another fuel pressure sensor a month passed same issues occurred at least 3 more times on 3 different occasions. I’ve had to get my car towed off the middle of the free way or road numerous of times. This has been a financial nightmare

NHTSA ID

11705470

Incident

Dec 16, 2025

Took car to Kia for an oil change and car started driving weird . Rpm hand running high. Check engine light came on , took car to Kia and fuel tank was expanded . Car is still not fixed , and Kia won’t continue to pay for rental.

NHTSA ID

11705201

Incident

Nov 24, 2025

Recall SC263) AIR BAGS THAT DO NOT DEPLOY (SC356)x2 A MELTED FUEL TANK CAN LEAK, INCREASING THE RISK OF A FIRE

NHTSA ID

11704826

Incident

Dec 12, 2025

Within three days of purchase, the vehicle experienced a fuel system failure requiring the gas tank to be replaced. Shortly afterward, the check-engine light illuminated, indicating additional engine or emissions problems. The failures occurred without warning and made the vehicle unsafe to drive. The engine warning has continued to appear, suggesting a recurring or unresolved malfunction. The defects create risks including fuel leakage, stalling, engine shutdown, and potential fire hazard. The safety of the driver and others on the road is put at risk because the vehicle may fail while in motion. The problem appeared immediately after purchase and continues to recur. The dealer was notified but refused to diagnose or repair the vehicle further. No manufacturer inspection has occurred because the dealership declined to provide service. The warning light first appeared within the first week of ownership and has remained intermittent. The vehicle shows signs of unstable engine operation and ongoing system malfunction. The issue has been observed by the dealer, but they declined to perform proper diagnostics or repair. The defects are persistent and pose ongoing safety concerns.

NHTSA ID

11704502

Incident

Sep 10, 2025

The contact owns a 2015 Kia K5. The contact received notification of NHTSA Campaign Number: 25V794000 (Fuel System, Gasoline). The contact stated that days before the vehicle was scheduled for an unknown recall repair, while refueling, the contact observed gasoline pouring out of the tank. The vehicle was taken to a dealer, where it was diagnosed, and determined that the fuel tank had expanded due to fumes being trapped inside. The vehicle was not repaired due to parts not being available for the repair. The contact stated that the manufacturer has exceeded a reasonable amount of time for the recall repair. The manufacturer was notified of the failure. The failure mileage was approximately 70,000.

NHTSA ID

11703986

Incident

Feb 15, 2025

Mileage

70,000 mi

For the past 16 months I have been experiencing a fuel odor in my vehicle cabin while idling or when in slow moving traffic. Knowing this likely is due to a fuel leak, I have taken it to the dealership 6 times to find the leak and remedy it. The dealership always finds something to repair/replace under warranty, however, the fuel smell persists. Over the past 16 months, this has increased in how strong the smell is and how often I am smelling it. It started out as only smelling fuel once a week or so. Now the smell is there during ever drive. It seems as though if my tank of 7/8 or above full, it does not smell for some reason. Upon searching online, many other K5 owners are experiencing the same exact issue and the dealership has been unable to resolve this. The vehicle has had 3 seperate recalls for fuel issues and I believe another is necessary regarding this because the recalls has not fixed the fuel leak I and many others are experiencing. Kia is doing the bare minimum to resolve this and my children are breathing fuel fumes consequently. Please note, not all my repair invoices are attached. I do not have access to all of them at this time

NHTSA ID

11700934

Incident

Jun 19, 2024