2011 Hyundai Sonata

On March 18, 2026 I brought my vehicle to AutoNation Hyundai for an oil change and full diagnostic. Your dealership’s own diagnostic report showed no knock sensor code, no engine issues, and no active warning lights. My car was fully drivable when I dropped it off. Within 30 minutes of picking my vehicle up, the check engine light began blinking and the car became completely undrivable. It has not moved since March 20, 2026 at the dealership. The dealership did an additional diagnostic and found a knock sensor that was not there during the first diagnostics and have stated that my engine has too many miles to be covered uder warranty.

My 2011 Hyundai Sonata experienced a flashing check engine light and entered limp mode (vehicle cannot accelerate), displaying diagnostic code P1326. This code is associated with Hyundai’s Knock Sensor Detection System (KSDS), which was installed as part of a recall-related campaign to detect engine bearing failure in Theta II engines. The vehicle previously had its engine replaced under recall due to known defects involving connecting rod bearing failure. The current condition renders the vehicle unsafe to operate, as it is limited in power and may stall or fail unexpectedly. The system is designed to detect potential engine failure, which is a known safety issue. Despite this, the dealership has not completed proper diagnostic procedures related to the KSDS system and potential engine failure. The vehicle has been out of service for approximately one month without resolution. This appears to involve a failure of a recall-related safety system (KSDS) and/or a recurring engine defect that Hyundai has previously acknowledged. My biggest concern is that they are diagnosing this issue as an electrical defect rather than the engine itself (which the system is design to warn about) in order to avoid having the repairs covered under the warranty that originated due to the class action lawsuit, and this component was only created and provided to consumers with no charge in order to protect the company from having to continue replacing defective engines

The vehicle suddenly stopped and died while driving. The mechanic confirms that the engine is gone, contact Hyundai. Ourisman of Rockville and Hyundai Motor America (HMA) refuses to replace the engine for free. The vehicle has now developed a severe engine knock consistent with the well-documented defect affecting Hyundai’s Theta II engines. Hyundai has publicly acknowledged this issue and issued a major recall covering approximately 470,000 vehicles with the following specifications: • Model Years: 2011–2012 • Engines: 2.0L and 2.4L • Manufacturing Period: December 11, 2009 – April 12, 2012 Hyundai and federal regulators identified the safety concern as manufacturing debris that could restrict oil flow to rod bearings. This defect can lead to engine knocking and eventual engine failure. Critically, Hyundai has acknowledged that engine failure may stall the vehicle while driving, significantly increasing the risk of a crash. Hyundai’s official remedy for this defect required dealerships to: • Inspect engines for bearing noise • Replace the engine if necessary • Honor Hyundai’s extended engine warranty of 10 years / 120,000 miles for affected vehicles. This issue has also been the subject of significant litigation, including the class action lawsuit Case No. [XXX], filed January 23, 2018, against Hyundai Motor America (HMA), Kia Motors America, Inc. (KMA), Hyundai Motor Company (HMC), and Kia Motors Corporation (KMC). Despite these well-known issues, Ourisman of Rockville failed to disclose any of the following when selling my daughter's this vehicle: 1. The widespread engine defects associated with the 2011 Hyundai Sonata. 2. The recall and safety concerns related to debris restricting oil flow to rod bearings. 3. The extended Hyundai engine warranty covering affected vehicles up to 120,000 miles. This omission is particularly concerning because this defect presents a serious safety hazard and a clear and present danger. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

The steering column gets loose because of a commonly defective bushing. The steering bangs and has free play making full control more difficult.

My car was broken into and they broke off my door handle and took out ignition parts, a police report was done

My 2011 Hyundai Sonata experienced sudden engine failure and the engine is now locked up. The vehicle became inoperable and had to be taken to a Hyundai dealership. The dealership confirmed the engine is locked and not drivable. Hyundai denied the engine replacement claim stating the vehicle has A04/A08 branding indicating the engine originates from a scrapped or rebuilt vehicle. However, Hyundai refused to provide any documentation supporting this claim. They also refused to verify the engine serial number against the VIN to confirm whether the engine is original to the vehicle. A NMVTIS vehicle history report shows the title status as ACTIVE with no salvage, junk, or rebuilt branding. Despite this, Hyundai continues to deny the claim without documentation. This vehicle contains the Hyundai Theta II engine that has been the subject of recalls and settlement actions related to premature engine failure. The failure pattern in this case matches the known defect where engines seize or lock up unexpectedly.

The contact owns a 2011 Hyundai Sonata. The contact stated that while driving approximately 30 MPH, the vehicle unexpectedly lost motive power. There was no warning light illuminated. The vehicle became inoperable and could not be restarted, and the vehicle was towed. The vehicle was towed to a dealer, where it was diagnosed with engine failure. The dealer stated that the failure was related to a previous recall associated with the VIN; however, the recall number was not provided. The dealer informed the contact that the engine needed to be replaced. The vehicle was not repaired. The contact was referred to the manufacturer for assistance. The manufacturer was notified of the failure but denied coverage for the repair and alleged that the engine failure was a result of negligence in the maintenance records. The approximate failure mileage was 183,000.

UNKNOWN - I noticed DASHBOARD crack over time and the AIR BAG light remain on at all times. The AIR BAG light on the passenger side shows OFF. The entire dashboard is cracked. I fear that I can no longer drive my car distances due to air bag issue. I did not report the issues to a dealer yet, I was waiting until next oil change time. I do not know the date that it started.

The contact owns a 2011 Hyundai Sonata. The contact stated that while attempting to start the vehicle, the vehicle failed to start as intended, and the contact noticed a strong fuel odor coming from underneath the hood. Upon inspecting underneath the hood, the contact noticed a leak. An independent mechanic diagnosed the vehicle and determined that the fuel line was leaking. The vehicle was not repaired. The contact related the failure to an unknown recall. The manufacturer was contacted, but only the automated system was available. The failure mileage was unknown.

There was no accident .Airbag light on the dash, on the driver side, remains on at all times. The airbag indicator on the passenger side says off. Dashboard has completely cracked, both sides and the center. Unknown incidents- I don’t know of any incidents.

The contact owns a 2011 Hyundai Sonata. The contact stated that while the vehicle was parked, an inspection revealed that the rear frame of the vehicle, located near the passenger’s side, was severely corroded. The dealer was contacted; however, the vehicle was not diagnosed or repaired. The manufacturer was notified of the failure and a case was opened. The approximate failure mileage was 148,757.

The contact owns a 2011 Hyundai Sonata. The contact stated that while driving approximately 65 - 70 MPH, there was a grinding sensation coming from the front wheels, and the grinding sensation was felt in the steering wheel. The vehicle was taken to the dealer, who diagnosed that the rod bearings and hubs had failed, causing the grinding sound. The contact was informed that the rod bearings and hubs needed to be replaced. The vehicle was towed to a certified mechanic, and the vehicle was repaired. The contact stated that while driving at various speeds the following day, there was a loud grinding sound coming from the vehicle. The sound also occurred while the vehicle was parked. While attempting to accelerate from 25 - 35 MPH, the engine started knocking, and the vehicle clunked and jerked. The vehicle decelerated, and the contact pulled over to the side of the road. The contact became aware that the accelerator pedal was not operating as needed. While on the side of the road, the contact turned off the vehicle and attempted to restart the vehicle; however, the vehicle failed to restart. The vehicle was towed to a certified mechanic, who diagnosed that the engine had failed, and the mechanic recommended the engine replacement. The vehicle was not repaired. The vehicle was towed to a different dealer, Capital Hyundai of Greensboro (801 E Bessemer Ave, Greensboro, NC 27405), and the contact was informed of NHTSA Campaign Number: 15V568000 (Engine). The vehicle was not repaired because the manufacturer stated that the maintenance history was not satisfactory enough to warrant an engine replacement. The failure mileage was approximately 138,000.

The Vehicle: "I have a 2011–2014 Hyundai Sonata with massive underbody rust." The Failed Fix: "Service Campaign 946 was completed on this car in 2017, but it did not work. The rust is now worse." The Safety Risk: "The structural metal is so rusty that I am afraid it will snap while I am driving. This makes the car unsafe." Hyundai is refusing to fix it because the car has a 'branded' (abandoned) title, even though the structural safety issue is still there."

I am reporting a safety-related engine failure involving my 2011 Hyundai Sonata 2.0T. In November 2025, at approximately 90,000 miles, the vehicle experienced a sudden engine failure while driving, including loss of power and abnormal engine noise. This created an unsafe driving condition and required the vehicle to be removed from service. Component/System Involved: The engine (Theta II 2.0T) suffered a catastrophic internal failure. The engine and internal components remain available for inspection upon request. Safety Risk: The sudden loss of engine power reduced my ability to maintain speed and maneuver in traffic, posing a safety risk to myself and other motorists. Confirmation and Inspection: The failure was confirmed by an authorized Hyundai dealership, which inspected the vehicle and documented the internal valve train condition through photographs. Hyundai Motor America reviewed the claim and issued a written denial. No independent third-party technical inspection was performed. Prior Symptoms: Before the failure, the vehicle had a history of excessive oil consumption requiring frequent monitoring and oil addition despite regular maintenance. Abnormal engine noise was present for approximately one minute before failure. No warning lights adequately predicted the sudden failure. Additional Context: This vehicle is equipped with a Theta II engine, which has been the subject of prior recalls and settlements related to internal engine defects. Hyundai denied warranty coverage alleging “exceptional maintenance neglect”; however, inspection photos show a well maintained valve train with no sludge or oil flow obstruction, only light surface varnish consistent with normal engine aging. I am concerned this failure represents a continuation of a known Theta II engine defect (confirmed by Hyundai technician who performed inspection with OBD code P1326 followed by engine failure) and poses a serious safety risk due to sudden loss of engine power while driving.

CRUISE controldoesnt work due to design defect dirt getting in and stopping the function.

The contact owns a 2011 Hyundai Sonata. The contact stated that while driving at an undisclosed speed and making a left turn, the vehicle experienced a loss of motive power. The contact was able to restart the vehicle; however, an abnormal knocking sound was heard, and there was smoke coming from under the hood. The contact was able to drive the vehicle to a nearby residence, where it temporarily remained. The contact attempted to drive the vehicle a few miles to qualify for towing, per the vehicle insurance provider. The vehicle was towed to a local dealer, where it was diagnosed with a rod bearing failure. The vehicle was not repaired due to insufficient engine oil maintenance records. The contact related the failure to NHTSA Campaign Number: 20V746000 (Engine). The manufacturer was made aware of the failure. The failure mileage was approximately 137,600.

The vehicle experiences a recurring defect where the brake light turns on suddenly and the engine shuts off while driving. The failure appears related to the braking system (brake switch circuit), electrical system (CAN-bus/ECU communication), and engine control (shutdown/stall). The system remains installed and is available for inspection upon request. The shutdown poses a serious safety risk, including possible rear-end collision or loss of power in traffic. The problem has occurred multiple times. The dealership inspected the vehicle briefly but failed to diagnose or document the defect and returned the vehicle within hours, stating “it shouldn’t be a problem,” even though the issue continues. Hyundai has refused to provide recall documentation or authorize a re-inspection. The only warnings prior to shutoff are the sudden activation of the brake warning light just before the engine cuts off.

The contact owns a 2011 Hyundai Sonata. The contact stated that while driving at an undisclosed speed, the engine started to overheat, with the check engine and temperature warning lights illuminated. The dealer was contacted. The vehicle was not diagnosed or repaired. The manufacturer was not made aware of the failure. The approximate failure mileage was 184,000.

I bought this car from someone in April of 2024 and the person who i bought it from said everything was perfectly fine, they brought it to the Hyundai dealership and according to the mechanic there the engine was fine….i have taken care of the engine since i bought the car, kept up with oil changes and everything….until a few days ago when the whole thing ceased up on me while driving down the road to my sons school. I wasnt going fast either, the speed limit is 40mph where i was when it happened, but I’m glad i have quick reflexes because otherwise we would have wrecked the car. Everything shut off on me and now its knocking. There is alot of metal shavings in my oil and my mechanic tried to drain it a few times to get the debris out of the oil but it does no good.

The contact owns a 2011 Hyundai Sonata. The contact stated that while driving at an undisclosed speed, the brake warning light illuminated, and the vehicle shut off. The vehicle was taken to the dealer, where it was confirmed that the failure was due to an unrepaired recall. The contact received notification of NHTSA Campaign Number: 23V651000 (Service Brakes, Hydraulic). The repair was performed. The failure reoccurred. The dealer was made aware of the failure; however, the failure was not duplicated. The contact was informed that the recall was closed. The vehicle was taken to an alternate dealer, where it was diagnosed with a failed hydraulic ABS booster sensor. The contact was provided DTC: C1237/HPU. The contact was informed that the hydraulic ABS booster sensor needed to be replaced. The vehicle was repaired. The vehicle was released to the contact; however, the failure reoccurred. The contact stated that the ABS warning light illuminated and then went off. The manufacturer was made aware of the failure, and a case was filed. The contact was advised to take the vehicle for a second inspection. The dealer declined to perform the second inspection. The contact was informed that the repair was not associated with the recall repair. In addition, the contact referenced several unknown recalls; however, the contact was informed that the repair was not related to a recall. The failure mileage was approximately 149,000.