Other Fuel System Problems of Hyundai Sonata - part 2

Multiple critical mechanical and safety issues have occurred with my 2018 Hyundai Sonata sport. The vehicle has experienced persistent engine misfire, a severe oil leak, emissions system failure, and extensive paint deterioration. A certified technician confirmed an active oil pan leak with no dashboard warning lights, posing a fire and stalling hazard. To prevent further damage, I replaced the entire oil pan and spark plugs at a personal cost of approximately $800 at firestone complete auto care. The check engine light revealed diagnostic code p0420 – catalyst system efficiency below threshold (bank 1). An o’reilly emissions scan confirmed the catalytic converter failure, and emissions status was marked “red. ” the vehicle will not pass an obd-based emissions test. At 149,219 miles, Hyundai refused warranty coverage due to mileage. A certified Hyundai dealership quoted $3,722 to replace both the catalytic converter and valve cover gasket, which remains unaffordable and unrepaired. In addition, the factory-applied white paint began peeling severely from the hood and roof. Although Hyundai issued a warranty extension for this known defect, the dealership refused to repaint the hood, citing a minor dent — even though the peeling is clearly unrelated. The exposed metal has started to rust, risking structural deterioration. All concerns have been evaluated by certified Hyundai service and independent professionals. These combined mechanical, emissions, and exterior failures raise serious safety and durability concerns. I am filing this report to document manufacturer-related defects that may affect other owners of this model and year.

See all problems of the 2018 Hyundai Sonata 🔎.

I had engine issues back in 2021. I had to pay $600 for a part to be installed to fix the problem . The engine failed, the idle was violently lurching forward and would randomly shut down. Recently the car shut down without warning again. Its scary.

See all problems of the 2016 Hyundai Sonata 🔎.

In early may 2025 while driving around 40mph, I heard a very loud pop which startled me. Pulled over and looked back and noticed my backseats were push up out of place. I attempted to put the seat back into place but it wouldn’t fit into the latch anymore. The framing underneath the seats looked pretty damaged so I took it to a local mechanic. After doing some research, he found information for a check valve/fuel tank recall (service campaign 9b1) and then advised me to go a Hyundai dealership. I attempted to take it to the dealership, whom sent me away after I advised them of what happened. I came back the next day asking them to take a look at while informing them about the recall that could be related. Later that evening, they called and said the issue was directly related to the recall and the repairs would be covered. My car was in their possession for from 5. 12. 25 to 7. 25. 25 without any updates or instructions on what is happening. I was told they’re waiting to hear back from Hyundai manufacturer on how to proceed. They returned my car to me on 7. 25. 25 stating everything was repaired. On 7. 31. 25 they called me back stating my tank needs to be replaced and bring the car back ASAP. My car was again being repaired and was returned to me on 8. 25. 25. Now my vehicle will not start randomly sometimes. At this point, I’m under the impression my vehicle is no longer safe as all the issues I’ve been facing are fuel related.

See all problems of the 2020 Hyundai Sonata 🔎.

Burns oil fast. 900 miles from an oil change the car oil stick was empty. There are no signs of oil leaking. Every 1000 miles you have to place oil back into it. I’m not the only one complains of this issue. I was reading on reddit and it’s thousands of people having the same issue.

Unknown, caught fire. ??.

See all problems of the 2013 Hyundai Sonata 🔎.

Fuel lines and connections / fuel tank band / fuel tank vapor vent system hoses [xxx]: my check engine light illuminated. I immediately returned to Hyundai riverdale. They advised me it could be the fuel tank and stated they needed to keep the car for 5-7 business days. May 1, 2025: I dropped off my car for inspection, having made arrangements for a personal rental car. May 7, 2025: I received a text message (no phone call) indicating the inspection was complete and was presented with a $3500 bill to replace the entire fuel tank. May 9 or 12, 2025: marilyn from Hyundai riverdale called me regarding my vehicle. She explicitly suggested I "contact your insurance company, advise them you hit something on the road, pay the deductible, and they will pay for the repairs. " she then stated, "I know you hit something after April 9th because your fuel tank is now damaged. " I denied hitting anything. During this call, she mentioned a "recall" related to fuel tanks on all Hyundai Sonatas, which I was never previously made aware of. I questioned why I was being charged if there was a recall for the exact issue I was experiencing. She claimed my car was previously checked and the fuel tank was fine, therefore the cost fell to me. May 14, 2025: merilyn called to inquire if my insurance would cover the repairs. I informed her I was picking up my vehicle as another Hyundai dealership in newnan was willing to perform the recall repairs for free. Upon arrival at riverdale, I faced resistance but demanded my car be released. I was then charged a $200 inspection fee, which I refused to pay. Marilyn then provided my keys and, upon learning I planned to drive to newnan, stated, "I wouldn't feel right letting you drive this car off the lot and something happening to you. Your vehicle at any moment can blow up due to the fuel tank. It's very dangerous to drive and suggest you get a tow truck. " April 11-may 1st I drove that vehicle w/no idea it had the potential to blow up. Information redacted pursuant to the freedom of informati.

See all problems of the 2022 Hyundai Sonata 🔎.

I received a notice in the mail my car needed a software update. I went to the dealership to have the update performed. They informed me there was a service campaign for an expanding fuel tank due to pressure. They were unable to return my car to me at that time stating they were awaiting direction from Hyundai motor of America for the fix. The fuel tank expanded so much it bent the body of of the car underneath the backseat. It also broke the support straps. The dealership stated it was a known issue with a vent valve. Causing the fuel tank to swell so much it damaged the body. They have had my vehicle for 9 weeks with no direction as to what to next.

On [xxx] at approximately [xxx], my [xxx] daughter was using my car to go to work. When she called us and informed my husband that the car did not start. At that point he asked to video call him so that he can visually see what was going on. She was directed to turn on the car again at and that point, the car started then smoke was noticed from coming out of the hood. My daughter managed to open the hood where flames emerged from the center of the engine. She then ran in the house to get a fire extinguisher and managed to put it out and it reignited. She then made a second attempt with another fire extinguisher where it briefly subsided and then grew larger. At that point the fire dept arrived and successfully extinguished the fire and deemed the car totaled after the fire marshall carefully inspected the car. Information redacted pursuant to the freedom of information act (foia), 5 u. S. C. 552(b)(6).

See all problems of the 2012 Hyundai Sonata 🔎.

Car is a Sonata hybrid limited equipped with a solar roof which charges the hybrid battery. Vehicle began to cut off battery power while parked, requiring the use of a factory equipped 12v override switch in March 2025 after approximately 3. 5 years of ownership. This occurred multiple times, often when the car was parked in the sun but independent of how long it had been driven prior or how long it had sat without being started. Evaluated by two Hyundai dealers; second dealer found a fault in the "solar dcdc converter" as well as the hybrid battery bulging. Battery module replaced. Unclear if this resolves the issue or it will recur again. Am speaking to Hyundai regarding battery warranty extension as vehicle had 88000 miles on it at the time of the issue starting. Online fora (e. G. , reddit, facebook) note other customers who have had similar problems with similar fixes. - [xxx] - [xxx] - [xxx] - one individual in this thread had complete power loss while driving down the highway this issue potentially risks stranding customers, and if the hybrid battery continues to bulge increases the risk of fire which could lead to property damage, personal injury, or death. Information redacted pursuant to the freedom of information act (foia), 5 u. S. C. 552(b)(6).

So my car started to stall when I started it an when I started goin down the road like it wanted to die. Then I started to smell gas very strong so had a code tester put to my car an I have 6 permanent codes. An not only that im smelling oil strong an noticing big oil spots under my car. So I look under the hood an behind the turbo I see oil behind an underneath the turbo. I definitely didnt feel safe driving but now its not even drivable. I purchased it couple months ago from an individual an I cant belive the amount of problems this car has. Im a single mom an trying to support my family an its hard to now with a non running car. I've put quite a few parts hoping it would fix some of the problems an nothing has. I absolutely love the car an very beautiful but unfortunately to many problems with it. Eninge, gas leaks, timing.

My wife and son experienced a terrible situation on the way home from training. They had to stop at the nearest gas station due to the vehicle showing extremely low gas in the tank during a short drive home. The fuel gauge initially showed about half a tank but drastically dropped on the way home. They stopped at a gas station to add fuel but during the process, fuel starting spewing out of the tank. The vehicle was scheduled to be dropped off at a later date for an open recall (service campaign 9b1). I called the dealership and told them I needed to get the vehicle in right away due to the incident. After bringing the vehicle to Hyundai, they told me that the fuel tank exploded causing the tank to swell all the way around. Because the tank is located under the rear seat, we constantly heard air coming in due to the rear seat not seating properly. The check engine also was on and we smelled fuel while driving the vehicle. Hyundai representatives has been avoiding my calls to the point where I had to go in person for an update. Apparently, a district manager had to come inspect the vehicle to advise the dealership how to write up the request to send to corporate.

Unknown cought fire under the hood was engulfed within minutes.

Service campaign 9b1 that my gas tank has explanded/exploded due to the issue noted in the subject line. As you can see the whole bottom of the backseats have been raised up imcluding the part that connects to the gas tank itself. My car is immobilized and not drivable during this time. What is the next step to take?.

I have had this car checked out 3 times and on my way to the 4th appointment. I can be in the middle of the road or pulled up in my driveway the rpms go crazy shuts off every light comes on then clicks and I have to waite and try to restart. This car has been a problem since we bought it brand new even the chrome has come loose on it. Took to 1 dealership they said it's not throwing a code so nothing they can do I pulled out of the dealership onto the busy highway and the rims went crazy lights came on and it died called the mechanic that said nothing was wrong he came out got it running took it back came back said nothing showing up so there was nothing he could do. I'm driving another 3 hours away hoping I make it to another dealership that said they would look at it after I sent pictures and a video to the mechanic. I will never buy another Hyundai again and definitely tell anyone I know not to.

See all problems of the 2023 Hyundai Sonata 🔎.

My 2018 Hyundai Sonata (approx. 60,000 miles) began consuming excessive oil, and the engine started smoking while driving. My wife barely made it to the dealership — the car was unsafe, struggled to stay running, and visibly smoked from under the hood. Hyundai acknowledged the oil issue but refused to cover engine replacement. Instead, they approved a one-time combustion chamber cleaning and requested we drive the car 1,000 miles to "see if it gets better. " this is a major safety concern. The vehicle is part of a group of Hyundai models known to have defective theta ii engines that have led to engine failure, fire risk, and recalls. This issue is widespread, and Hyundai is not taking proper responsibility for defective engines in cars like mine.

I experienced an issue where the gas tank in my 2020 Sonata began to swell and emit loud popping noises while the vehicle was parked. I took it to the dealership, and Hyundai corporate eventually acknowledged the issue and agreed to buy out my loan. However, no official recall has been issued for this model year. This problem has had a major impact on my life. I lost my job due to not having transportation for over two months, and the stress of not knowing whether my vehicle was safe made it even worse. I had to upgrade my insurance for a loaner I never received, take financial hits, and go into deeper credit trouble—all while also recovering from a serious injury from a previous car accident. I now have to start over with a new loan while my credit is already damaged. I’m submitting this report not just for myself, but to ensure that other 2020 Sonata owners are protected and made aware of this issue. I believe this is a serious defect that warrants official investigation.

Fuel system expanded back seat.

The affected component is the engine/rod bearing (theta ii 2. 4l). My 2011 Hyundai Sonata stalled and the engine locked up twice in live traffic (March 2025 and July 2025). The vehicle is available for inspection if needed. This created a serious safety risk to me and others on the road, as the stall occurred on [xxx] at highway speeds. This failure could have been catastrophic had it happened on the DC/baltimore beltway or another high-traffic roadway. Hyundai’s system shows recall 132 was marked complete at very low mileage (around 32,000 miles), but my vehicle later developed oil consumption and stalling consistent with rod bearing failure. Capitol heights Hyundai noted a warranty pre-authorization (PA) in March 2025 and told me Hyundai needed my mailing address “for the claim,” but later said it was a typo and that no record exists. The dealership charged me for a diagnostic but did not inspect the vehicle for rod bearing failure, despite symptoms consistent with recall 132. Annapolis Hyundai, where the car was purchased as a cpo, has admitted they have no documentation that recall 132 was ever performed (no repair order, mileage, or technician notes). Yet Hyundai’s system shows recall 132 marked “complete. ” without proof that the ksds software or bearing inspection was done, I belive this recall should be considered open. Hyundai consumer affairs has stated that I must pay for towing and diagnosis before they will investigate, with possible reimbursement later. This conflicts with federal law (49 u. S. C. § 30120), which requires recall diagnosis and repair at no cost to the consumer. Prior to the failures, my vehicle had a history of oil consumption and “no oil on dipstick” findings, which are known precursors to rod bearing failure. No warning lamps appeared before the stalls. I am requesting NHTSA’s assistance in requiring Hyundai to provide documentation or reopen recall 132 and perform a no-cost inspection/repair to ensure this vehicle is safe to operate information redacted pursuant to the freedom of.

See all problems of the 2011 Hyundai Sonata 🔎.

The car would excelerate while in park. While I was pressing the brakes the car would jerk forward, it would not just quietly idle. While driving the car would randomly speed up or slow down. Sometime it would sound like it was going to shut off and start vibrating.

See all problems of the 2021 Hyundai Sonata 🔎.

On [xxx], in washington, d. C. , my 2013 Hyundai Sonata experienced sudden engine failure, leaving the vehicle inoperable. My goodwill repair request was denied within 30 minutes, without a proper inspection of the rod bearings (a known failure point covered under the txxi extended warranty) or the fuel pipe recall—a known issue that could pose a fire hazard. Hyundai cited suspected maintenance neglect, but I have documentation of regular synthetic oil changes. Despite having over 200,000 miles, a firestone inspection from September 2024 confirmed the vehicle was in good condition prior to the failure. Additionally, Hyundai theta ii engines are widely known to suffer from excessive oil consumption, a defect that can lead to premature engine failure even in well-maintained vehicles. Hyundai has replaced engines in vehicles with similar mileage under the same extended warranty, yet in this case, no proper inspection was conducted before denial. Safety concerns: the fuel pipe recall was not inspected, raising concerns about whether unresolved recall defects are leading to engine failures or fire risks. The airbag clock spring, covered under Hyundai’s txxa extended warranty, was not inspected, despite the airbag light being illuminated, potentially affecting airbag deployment in a crash. The vehicle failed without warning lights or error messages, creating an unsafe situation. Hyundai’s failure to inspect recall-related issues before denying repairs could impact other affected vehicles on the road. I request that the NHTSA: ensure Hyundai properly inspects recall-related components before denying repairs. Investigate whether Hyundai is improperly denying warranty and recall-related repairs, even in cases where similar vehicles have received replacements. Determine if the unresolved fuel pipe recall and airbag clock spring defect pose broader safety risks. This issue has been reported to Hyundai corporate, but no proper inspection has been performed. Information redacted pursuant to the freedom of informatio.

Car keeps jerking also it’s something going on with the fuel injections I’ve had to get them replaced twice. Please help.

I took my car in for a standard oil change and tune up. They found out that the fuel tank had expanded to the point where it caused significant damage to the metal frame. The Hyundai dealership sent it to the local body shop for an estimate for the frame, they sent it back because the dealership hadn't removed the gas tank, then the dealership sent it back to the body shop. It's been 3+ weeks, my car is still in the shop, and I haven't received any indication of whether my car is able to be fixed. The dashboard never displayed any warning messages and there were no symptoms of the problem. I had no idea the gas tank had expanded and could've caused an explosion or fire.

Took my car in February 10 for a recall that pop up on the app and today is June 22 and I’m getting all the run around and different dates for my car to be ready but everything it’s time to pick up my vehicle something comes up and they told me they took my car back to the body shop for the recall issue. All the information are added on the file.

The vehicle has begun to vibrate/shake badly but manageable. When a code reader was connected to the vehicle both codes 7e9 and 7e8 showed up. Upon researching, information has been found that these specific vehicles have been known for recalls due to fuel hose issues. If I continue to drive this vehicle without the issues being resolved which is not my fault, I jeopardize my son and I’s lives as well as any potential future passengers.

I had bought this car off facebook marketplace after confirming with my dad that it was a good car, when I had finally saved enough. After I took it home the check engine light had come on not too long after, the engine stalls when turning the key, pressing on the brake helps start the engine. Turns out the car was a salvage title and my dad didn’t know that and I didn’t know what that was.

Check engine light came on with a odb code of p0300. Engine started to run rough and mileage dropped substantially. Upon arrival to my home due to safety issues I turned off car and and let it cool. My father read the odb with a code reader and said it smells like gas but we will look at in the daylight. Today upon removing the engine cover and checking the spark plugs we discover stains and residual stains on the ignition coil packs and directly under the low pressure fuel line where it connects to the high pressure fuel pump. It seems the plastic clip/connector is leaking at anout the rate of one substantial drop per 3-5 minute period. This could cause an out of control engine fire. Dealer was contacted and while there are two recalls regarding other 2014 hyndai Sonatas for the same exact problem that this VIN was not covered by the recall and the repair cost would be 300 for the fuel line plus labor.

See all problems of the 2014 Hyundai Sonata 🔎.

My gasoline delivery hose/line/pipe/fitting is leaking near the spark plugs as checked by a tire plus mechanic. The car is not safe to drive. Hyundai refused to fix my car under the campaign 22v312000 that addresses this specific issue. They would not even open the car to see the pipe leaking. I would like to know if my car can be added to the campaign 22v312000.

When driving. Slow down to turn or to use round about car goes into ev. When I go to accelerate the gas motor will not re engage and the hybrid alarm system will go off. I lose all power to go any where. I have to pull over shut my car off give it a min then restart so the motor will come back on so I can drive again. I have to do this mulitple time in a 20 mile drive.

I was driving into work on a major road (about 45 mph) when my 2023 Hyundai Sonata stopped accelerating and my engine gave out. Initially I thought I was accidentally pressing on my break pedal but when I realized I wasn’t pressing the break, I had just enough time to turn on my hazards and get out of traffic and onto the shoulder of the road. I was stuck between a main exit and the major road. My battery, oil, and engine lights came on (no service lights had been on prior to this incident) and my car was just very slowly rolling before it automatically engaged my parking break - which makes me fearful of what would have happened if I had still been in busy traffic. I could gotten very badly rear-ended. My car only has just over 5600 miles and I never had any issues with it before and kept up with the general maintenance. I attempted to restart my car to no avail and about 30 minutes later I was able to restart my car but there was a very strong vapor smell in the cabin of my car. I got my car towed to a dealership and was informed one of my fuel injectors was misfiring/gone bad - similar to many other incidents on this site. I asked the dealership if they were able to view the state of my other fuel injectors and was told they were unable to do that, so I am unsure if other fuel injectors will go bad in the future.

Good afternoon. My issue is related to an existing recall that Hyundai motor sent to me back during the beginning of January 2025 for a gas valve, tank inspection (replaced if necessary. ) and ecu computer update. I've been to a total of 4 Hyundai dealers and none of them have been consistent with this recall. The first dealer is "future Hyundai" in concord, California. Initially, I'd took my car there for both recall and sound coming from the gas tank and my fuel level dropping. I was told by a service advisor by the name of hayley, that it would cost a diagnostic fee to locate the issue. I didn't have the fees. But, seeing that the gas tank was part of the equation. It was free. The gas tank inspection was never done. I was told by hayley that the fuel valve was replaced. But they mechanics only done a quick visual. I wasn't reassured that my issue was resolved. So I'd took it to a another Hyundai dealer. This dealer told me that part of the procedure is to take off the tank and inspect it. I didn't get that far because I was told that a tool that was used is used to take off the tank was broken. A bleeder tool. Which doesn't make sense, because the tool is used for bleeding out air from the fuel system. "allstar Hyundai. " the last two of the 4 dealers, "san leandro Hyundai" and "freemont Hyundai", told me that my fuel pressure hose in my gas tank and had swelled up. San leandro dealer told me that my gas tank expanded. But the "freemont dealer" only mentioned the fuel hose. But never mentioned the gas tank. But decided to add it anyways. None of these dealers have been consistent regarding the recall. "freemont Hyundai", the last of the 4, the service man told me that my tank is available. But his story changed from the time that I can get the job done 4 times. To having to have my car for two days before they can order the part. He'd order the parts, verified to me, when I was at my appointment. But now that conversation changed.

The engine shuts off, doesn’t start, check engine light flashing, losses power, jerks while driving it, I will get it up yo speed then will shut off or won’t move.

The car will randomly lose acceleration and jerk forward. It will make a beeping noise while the hev system warning flashes on the dash. It also says to turn off engine. While the warning is flashing and engine light is on it goes into a limp mode and you have limited acceleration. It has almost caused multiple wrecks when I go to acceleration from turning or at lights in traffic because I cant go over 20-30 mph. I have turned the car on and off and the hev system and engine light turns off and the car continues to work normal. It eventually comes back on and does the same loss of power/hev warning. It will be random and does not matter on how fast you are going to trigger the warning lights and loss of power.

Gas smell on the passenger side front seat.

See all problems of the 2015 Hyundai Sonata 🔎.

- component or system that failed: engine (cylinder #4 misfire) - safety was put at risk twice: once when knock sensor went off on interstate (October) and engine went into limp mode (aka protection mode). Required a tow from the, which was tricky with a vehicle full of passengers. Safety was put at risk gain when vehicle began to stutter/sputter on interstate (December). Drove 4-cylinder vehicle essentially on three cylinders an hour to dealership - problem has been confirmed by dealer (southern states Hyundai, raleigh, nc) - vehicle has been inspected by warranty inspector, who requests approval before disassembling engine to diagnose issue. However, based upon maintenance records and manufacturer's history of engine issues (more on this below), owner should not be liable for investigating a well known issue. At the time of this writing, the issue has been escalated beyond the dealership and warranty to Hyundai motor America, and currently awaiting the results of their findings. - symptoms of the problem include constant oil leak from vehicle purchase in may 2024 up to engine failure in December 2024. Various temporary remedies (oil changes and repairs, including oil drain plug gasket replacement, crush washer replacement, and replacement of cracked oil pan) did not fix the issue. Additionally, in the October incident, Hyundai dealership (sport durst Hyundai, durham, nc) simply updated the knock sensor detection (kds) software, despite the vehicle previously receiving the update in 2019 (this can be verified). Finally, owner, noted "engine knocking" (aka 'tapping') in vehicle prior to engine failure. - Hyundai (the manufacturer) settled a class action lawsuit in 2021. Vehicle is one of the vehicles listed under class vehicles, but dealer, nor warranty company, nor Hyundai seem to want to resolve issue, which both alienates owner and presents a safety hazard, as the vehicle is unsafe to drive. All claims here will be supposed via documentation and images.

The low pressure fuel line connector to the high pressure fuel pump failed and sprayed fuel over the hot engine. This could have easily cause a vehicle fire and death. This is a know issue and is covered by a safety recall on 2013-2014 Hyundai Sonatas (Hyundai technical service bulletin 20-01-030h). The same issue occurred on this 2015 Sonata that was built in June 2015. A temporary repair had to be made until Hyundai could inspect it. Vehicle was taken to holler Hyundai in winter park, FL and inspected. Results were forwarded to Hyundai motors America and the repair was declined because the 2015 models were not included in the recall. It is our belief that the same connector was also used on some 2015 Sonata models prior to the issue being discovered.