After the emissions 9c2 recall car hesitant when changing an Hyundai has knowledgement of the problem but don’t have a fix
- NHTSA ID
- 11743836
- Incident
- Jun 2, 2026
Owner-reported complaints naming the powertrain system, filed with NHTSA
Data refreshed
Powertrain reports that are not specifically the engine or transmission — driveshafts, axles, transfer cases and differentials. Every record below is an owner-reported complaint about the 2016 Hyundai Sonata submitted to NHTSA — not a confirmed defect, not a recall and not a manufacturer bulletin. 59 reports on file name it.
Complaints are reports submitted by owners and drivers to NHTSA. They are not verified and do not establish that a defect exists.
The 25 most recent of 59, in the owner's own words
After the emissions 9c2 recall car hesitant when changing an Hyundai has knowledgement of the problem but don’t have a fix
Went from 65 and dropped down to 40 going up grades on the freeway. Started shaking, check engine light went on and electric battery disappeared from dash. Got to top of grade, went back to normal. Problem repeated on next grades. Car had just left dealership lot an hour prior where it was safety inspected and they said all was fine. Took back to dealership for inspection and they said that there were no codes showing for what happened and all was well with the vehicle, when obviously it was not.
The following mandatory software update was performed on my vehicle: ECU SOFTWARE UPDATE FOR THETA II EMISSIONS IMPROVEMENT (SERVICE CAMPAIGN 9C2). After this update my vehicle drivetrain is quite erratic. In particular when the engine is cold it appears to jerk even when in Parking gear position. When cold the drivetrain experiences erratic gear shifts. This provides little confidence when driving and could result in safety issues when merging into traffic. Once the engine has reached its normal operating temperature it still makes occasional gear shift that are jerky and probably not good for the transmission. This vehicle had a very smooth transmission prior to the ECU software update, now I am hesitant when I need to merge into traffic, since I am not sure it will select the correct gear when accelerating. I have reported this to the dealership and Hyundai corporate service center and both indicate that when the engine is cold that the drivetrain can act strange, but once it is up to temperature it should be smooth. I have looked on the web and noticed multiple Hyundai owners with similar engines reporting the same issue after this software update. Hyundai may have satisfied the EPA requirements with this software, but they may have a created a safety issue for the vehicle operator and their passengers.
My 2016 Hyundai Sonata is experiencing severe oil consumption due to a known Hyundai engine defect. The engine burns oil rapidly and loses more than a quart between oil changes. This creates a safety hazard because the engine can stall, seize, or fail while driving. The Hyundai dealership did NOT perform the official Hyundai oil-consumption test. They only checked the dipstick, noted the oil was low, and submitted a request for a paid combustion cleaning. Hyundai declined to pay for the cleaning, and the dealership is refusing to perform the required oil-consumption test unless I pay $750.00. Hyundai Corporate also refused to authorize the test, stating the vehicle is out of warranty, even though this is a known engine defect affecting many Hyundai vehicles. Without the official test, Hyundai will not review the engine defect or consider a goodwill engine replacement. This is a safety issue because the engine can fail without warning. The dealership and Hyundai are refusing to perform the required diagnostic test unless I pay $750, and refusing to review the defect without that test.
I have a car covered by the Theta II Settlement. Engine, fuel system. Metal shavings found in oil and oil is diluted with fuel and oil if overfilled 1 inch above full mark on dipstick upon pickup from dealership. The vehicle is available for inspection at my residence; however, it is currently grounded as a known safety hazard. The vehicle is exhibiting symptoms of imminent engine failure (audible knocking, P0011 code, and oil dilution). Despite being shown evidence of this(photo and video of oil overfill and watery viscosity) , the manufacturer instructed me to continue operating the vehicle, placing myself, and other drivers at risk of a high-speed collision or vehicle fire. The symptoms (P0011 code and engine noise) were confirmed by an independent mechanic on March 25th 2026. However, during the official Bearing Clearance Test (BCT), the dealership intentionally overfilled the engine oil by 3 quarts (documented via photograph) to muffle mechanical noise and artificially pass the diagnostic and issued a pass on all inspections despite the oil hazard. Hyundai Corporate Case Manager Nikulmar Dhabi has admitted on record that the dealer was out of compliance by "being outside the standard notification time" yet they refuse to provide a safety-compliant remedy. Warning Symptoms & Appearance: Symptoms first appeared months ago when I repeatedly got a P0011 code, however On march 24th 2026 I received an engine light with a P0011 and the car going into limp mode while i drove. Warning signs included a persistent Check Engine Light (P0011) and audible metallic knocking. Upon checking the oil myself after the dealer "inspected" it, I discovered the oil was 3 quarts over the "Full" line, which is a deceptive practice used to mask rod bearing failure.
This complaint is NOT related to the existing recall associated with this vehicle. The vehicle is experiencing a serious loss of power and acceleration issue. The car is unable to accelerate past approximately 60 mph. When pressing the accelerator fully, the vehicle does not respond or increase speed. While attempting to accelerate, the engine RPM increases and then suddenly drops repeatedly, causing the vehicle to struggle to maintain speed. This behavior is consistent and occurs during normal driving conditions. This creates a dangerous situation, especially when merging onto highways or attempting to accelerate in traffic, as the vehicle cannot respond when needed. The issue has occurred multiple times and makes the vehicle unsafe and unreliable to operate.
The contact owns a 2016 Hyundai Sonata. The contact stated that while driving and depressing the accelerator pedal, the vehicle failed to respond or exceed 30 MPH. The contact stated that the speedometer reading was lagging. The contact stated that the vehicle accelerated as intended while depressing the accelerator pedal with more force. The vehicle was taken to an independent mechanic, where the camshaft position sensor was replaced. Additionally, the contact stated that the starter was previously replaced due to the engine's failure to turn over while starting the vehicle. The contact stated that upon switching to Sport Mode and driving 40 MPH, the vehicle jerked and lost motive power. The contact shifted to neutral(N) and was able to pull to the side of the road. The vehicle was able to restart the vehicle, but the vehicle was undrivable. The vehicle was towed to an independent mechanic, where it was determined that the failure could be an electrical failure or that an engine replacement was needed. The vehicle was not repaired. An unknown dealer was notified of the failure, but the vehicle was not diagnosed or repaired due to the cost. The manufacturer was not notified of the failure. The failure mileage was approximately 152,000.
My 2016 Hyundai Sonata (2.0T/2.4L engine) has been experiencing loss of motive power and severe engine stumbling at stoplights, creating an unreasonable risk of a crash in traffic. The Check Engine light is on with DTC P0010. Upon inspection, the internal oil seal plug at the intake camshaft E-CVVT has become unseated, causing an active oil leak. This matches the exact defect and symptoms (elevated idle of 1,200–1,400 RPM and power reduction) described in Hyundai Service Campaign TX3 (TSB 15-01-022-1). While that campaign only applied to 2015 models, my 2016 vehicle has suffered the identical failure. I am requesting that this safety-related defect be investigated for 2016 models to prevent potential engine fires from oil leaks or accidents from sudden power loss
Subject: Excessive Engine Oil Consumption – 2016 Hyundai Sonata I am reporting an ongoing and excessive engine oil consumption issue with my 2016 Hyundai Sonata that I believe may represent a safety defect or other significant reliability concern. The engine is burning oil at a rate far beyond normal expectations (requiring frequent top-off well below recommended mileage intervals), resulting in dangerously low oil levels while driving. I have maintained the vehicle per manufacturer recommendations and documented oil add-ins and dealer visits, but the problem has worsened over time. Despite presenting this problem to my Hyundai dealership, they have declined to authorize engine cleaning or further corrective action due to the mileage. I am struggling with high oil consumption and potential risk of engine failure while driving. This issue is not unique to my vehicle — numerous similar complaints exist in Hyundai forums and in other owners’ submitted complaints (e.g., reports of more than 1 quart consumed every ~500–1,000 miles and sequences of denied repairs) which suggests a broader pattern of oil consumption failures for this model year. Auto Safety +1 I believe this may represent a safety defect because loss of engine oil can lead to engine seizure or failure without warning, increasing the risk of a crash or injury. Please review this complaint, add it to the NHTSA vehicle database, and contact me if further information is needed.
Oil pressure sensor failure caused oil to leak into the injector harness damaging components and engine shutdown. Because this was a sudden engine shutdown and safety-related loss of motive power caused by an oil pressure sensor failure this presents a safety risk
Vehicle stalled while driving
On November 10, 2025, my 2016 Hyundai Sonata Hybrid (VIN [XXX] , approximately 150,000 miles) experienced a sudden loss of power while I was turning right and accelerating into traffic. The vehicle immediately entered limp mode with flashing warning lights and audible alerts. The vehicle lost normal propulsion and could not accelerate properly, creating a dangerous situation as it was blocking a traffic lane. I was forced to limp the vehicle into a nearby parking lot to get out of traffic. The vehicle was not safely drivable afterward and was towed home. A few days later, the vehicle was towed to Murdoch Hyundai in Lindon, Utah, for diagnosis. The vehicle was found to have diagnostic trouble code P1326, which Hyundai identifies as activation of the Knock Sensor Detection System (KSDS) related to connecting-rod bearing wear. This condition is part of Hyundai’s known engine defect and safety recall/warranty extension programs. During inspection, the dealer observed that the valvetrain did not show signs of neglect or sludge, which is inconsistent with oil starvation or severe maintenance neglect. This further supports that the failure is consistent with the known connecting-rod bearing defect addressed by Hyundai’s KSDS safety recall, rather than a maintenance-related issue. This is a safety issue because sudden loss of propulsion or reduced power while entering traffic creates a high risk of collision. Hyundai customer care has been unwilling to open a new case number or escalate review, and the dealer has indicated possible denial of engine replacement coverage based on incomplete oil-change records, despite the vehicle exhibiting the KSDS safety condition. I am requesting NHTSA review of this safety-related defect and the manufacturer’s handling of KSDS/P1326 failures. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
The vehicle experienced an engine and power train failure while driving on the highway, resulting in sudden loss of power. The electrical system also failed after the dealer visit, causing the battery to die every morning. Yes, the vehicle is available for inspection upon request. My car suddenly lost power on the highway and would not accelerate, forcing me to pull over on the shoulder with traffic moving around me. This created a serious risk of a rear-end collision or crash. Additionally, after the dealer visit, the electrical system began failing and the vehicle has been completely dead every morning, leaving me stranded with a child and unable to reliably start the car. The problem has not been reproduced because the check engine code cleared itself after the incident; however, the symptoms absolutely remain. The dealer refused to diagnose the loss-of-power event because the code was cleared, and they returned the vehicle to me with a dead battery. The electrical issue (car dying every morning) has been happening consistently since the dealer visit. The vehicle was taken to a Hyundai dealership immediately after the incident, but they refused to diagnose the loss of power due to the code being cleared. A mobile mechanic scanned the code at my home before the tow, but the code disappeared afterward. The electrical failure began after the dealer visit and has not been properly inspected by Hyundai. Yes. While driving on the highway, the check engine light came on and the car immediately lost power and would not accelerate. After the dealer visit, the car has been completely dead every morning and requires a jump to start. These symptoms began on the same day as the highway incident and continued after Hyundai serviced the vehicle.
High engine oil consumption 2 qts every 1k miles.
My vehicle had the following symptoms: 1. Alternating between sluggish acceleration/handling AND rough acceleration with the vehicle lurching forward at times 2. Check engine light with error code P00010 3. Occurred frequently over a one month period (5+ times) This was unsafe as the car could not properly accelerate and would lurch forward at intersections. This could easily have led to a crash. We limited driving. This issue was observed at the dealer where I repaired issue. The issue is exactly the same as the issue described in the recall for Hyundai Sonata 2015 under SB-10058136-4434 and was resolved by replacement of the E-CVVT seal as described. This issue is ridiculous for me to deal with and put my family as risk given it a KNOWN issue for Hyundai in their other vehicles.
Car Lost Power going up a hill. Generating codes P1326, P0455 and P0302
What component or system failed or malfunctioned, and is it available for inspection upon request? Automatic transmission failed two times. How was your safety or the safety of others put at risk? Vehicle stalled in the middle of the road while driving which put me and my family in a very dangerous situation Has the problem been reproduced or confirmed by a dealer or independent service center? Yes Has the vehicle or component been inspected by the manufacturer, police, insurance representatives or others? Yes, inspected by dealer and extended warranty Were there any warning lamps, messages or other symptoms of the problem prior to the failure, and when did they first appear? None, Tranmission failed without any warnings or check engine lights.
Background Info : On November 28th, 2023 I filed a case with Hyundai Consumer Affairs due to smoke and sparks coming from my 2016 HYUNDAI SONATA engine. I was assigned to a Case Coordinator Carla who did not provide her last name at telephone 714-694-4963. She was my contact person for the repair. I signed a tow authorization on November 28th , 2023 authorizing HMA to tow the vehicle to the nearest Hyundai dealership due to some delays in coordination on behalf on my contact Carla and the dealership Pohanka Hyundai received my vehicle on approximately December 4th, 2023. Per correspondence from Carla she had contacted the dealership with no response until the 18th of December 2023; approximately two weeks after the dealership received my vehicle. She informed me that she had made countless attempts to reach a service team member for follow up on an inspection. On December 18th 2023 I got in contact with Joseph to inquire as to what his inspection found. He stated “That he did not see an oil leak and the car hand no oil.” I explained to him that was my car had been recently serviced at Jiffy Lube on August 1st 2023 at 44,664 miles for an oil change. Per Hyundai the oil should be changed every 3,000 to 5000 miles which I had not exceeded as my car had 46863 miles at the initial time of the service inspection that he performed. He then said “Jiffy lube did not put any oil in the car then” which was impossible. I made contact with the Jiffy Lube location who performed the oil change to get the record of my last oil change as Joseph had a differing opinion. I was informed that in fact the oil was changed and they could provide video proof if necessary. I then communicated this information to Joseph as well as provided a copy of the last oil change. I then was told that I needed a CVVT replacement, transmission flush and oil change. I attempted to address his initial diagnose of “no oil in the car” as I had proof that it had been changed and that they should do furthe
I have a 2016 Hyundai Sonata that has had repeated engine issues including stalling overheating and shutting off. The car engine also caught on Fire on [XXX} and was reported to Hyundai Consumer affairs where a case was opened. The car was in the dealership for repair until [XXX] I have a warranty that the dealership or Hyundai did not honor for the engine, power train. The services that were repaired was a replacement of a engine piece which is Continuously Variable Valve Timing) System which controls the controls the open & close timing of intake valve to improve engine performance. On approximately [XXX] 3 days after picking the car up which I had to incur the cost of the repair as Hyundai did not honor my warranty the engine as well as oil light came on The car repair included transmission oil flush and engine oil replacement per the dealership. I contacted the service manager Mr Espinoza who was overseeing my case and informed him of the continued issues he asked me to drive the vehicle in to be looked it. as we have had inclement weather in my area i was unable to take the vehicle in. On [XXX] I attempted to drive the car to the services department at Pohanka hyundai only for the engine to make a roaring noise and stall also there was no engine oil in the car wherefore it should’ve been. I contacted the dealership and told they were busy and to bring it next week. i am requesting hyundai to buyback the car. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
INTAKE CAMSHAFT CVVT COVER AND SENSOR INTAKE CAMSHAFT CVVT OIL PLUG PLUG Exhaust Manifold I am up to date on all me oil changes and everytime I get and oil change the oil goes so fast! This has actually been happening ever since I got the vehicle. My acceleration has been decreasing when I get an oil change.
I am having electrical issues with my 2016 Hyundai Sonata plus the other recalls. It started as issues with the lights on the driver side. I have replaced several bulbs and the entire light even and still have issues with the lights working properly. Now the issue is the battery, alternator or the starter. The starter had to be replaced as I was advised by Hyundai dealership when my engine had to be replaced, per recall. I had to purchase a starter, that was three times the amount at the dealership because the one that is manufactured in the auto stores is not correct, so it should not be the starter as it is only 1 to 2 years old. I have had the alternator replaced as well as 2 batteries and I’m still having issues. It cut off completely while driving on more than 1 occasion. There was no warning, no power steering, gear lock, no lights & no power so I could not move and almost had a major accident. It is definitely a safety hazard even after the repairs, it has happened again! My vehicle is currently not working because the new battery will not hold a charge and they both have been replaced. I’ve been having other electronic type issues with this vehicle. My information center has not worked for the past 8 months or so! I reported this to Hyundai and they agreed that it could be a part of a previous recall, and advised me to go to the dealership to have it repaired. The dealership refuses because they don’t have required information to show it as a Current recall and want to charge me half the price of a new car to repair. I am not the only one experience this as my research has led me to several other Hyundai owners experiencing the same issues. It is not fair that they cannot be corrected as these are things that are none of consumer fault & should have been high demands to proper repair or recall being a major safety issue as it can cause a horrific accident! Shame on Hyundai for putting their Hyundai customers at risk & through so much chaos!
I keep having the same issue with this vehicle's fuel/propulsion system, power train, engine, cruise control. This vehicle is need it's fuel system cleaned now for a 3rd time in less then 2 years. I have done the high mileage maintenance on it as well. I drive the vehicle less than 5,000 miles a year. When I am driving the vehicle, it struggles to speed up, making me press on the gas repeatedly to get to the indicated speed limit. The vehicle does not slow down as it should when pressing on the brakes. I have to press repeatedly over and over and harder on the brakes in order for it to slow down. The vehicle jerks, speeds up without me pressing on the gas and sometimes it will not stop when prompted. I cannot put this vehicle on cruise control, because it speeds up and out of no where, it accelerates causing me to almost collide with another vehicle or object. Even when the vehicle is not in cruise control, the sudden jerks and acceleration puts me, my children and others in harm when it suddenly speeds up, jerks or will not stop in time. It makes a loud noise and jerks even when the car is in a resting position. It loses power, it speeds up when i need it to stay the same speed or slow down. I fear this vehicle is unsafe. I have reported these issues and a few more to the dealership who never responded, so I had to go over their heads, then finally I got a response from their Consumer Affairs' Department, as well as the BBB and they state because of the vehicle's age and/or mileage there is nothing they can do about it. Please help me. This is the only vehicle I have, and I am a single parent who cannot afford another vehicle. What is going on with this car? Why do I have to keep struggling to pay for something to get fixed and it is still not solved. Below, it ask for a date, but it is multiple dates, not just one. I have listed the first time it occurred. Thank you.
The paint on the vehicle is peeling. It started on the roof and has progressed to the hood, frond fenders, and trunk. Because I am not the first owner, Hyundai will not not cover repairs. On 23 Aug 2023 I also had to replace the transmission at 115,416 miles. Again, Hyundai refused to cover any repairs.
My vehicle is experiencing high oil consumption. An oil light came on for about a second and went out. When I returned home, I checked the oil, and it was empty. We have our oil changed at our dealership everyou 3000-3500 miles. The next time frame, I checked the oil regularly and noticed it was getting low very quickly. When we returned to the dealership we were put on a 1000 mile oil consumption test, then the next time had a combustion chamber cleanse, and then returned at another 1000 miles and the dealership disputed the amount of used oil, and told us if there were additional issues we would need to start over. It continues to burn unusually high, but we are monitoring it. Hyundai says their threshold is a quart every 1000 miles.
We have a Hyundai sonata that has been burning oil since 56,000 miles and has failed 5 oil consumption tests.the car is unsafe to drive. It stalls on highway and around town. It just stops running and leaves us stranded. The car now burns 4 quarts of oil every 1,000. We have to put oil in the car every week. The plugs fowl about every 4,000. . Car goes into stall or safe mode. We are afraid to drive the car and it's our only form of transportation. Hyundai just laughed at us. We have all maintenance records and still they won't fix the vehicle. We need help. The care is unsafe to drive because it stalls in traffic and we have almost been hit in the rear many times. This company made bad and defective motors yet our government refuses to protect us.
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