2017 Hyundai Sonata: engine knocking or ticking

Filed Sep 22, 2026 · Engine · CA

I am reporting an unaddressed, critical safety defect involving the Theta II engine in my 2017 Hyundai Sonata. The engine has developed a severe internal metallic knocking noise consistent with connecting rod bearing failure—the exact manufacturing defect associated with Hyundai's major engine recall campaigns (such as Recall 198 / Campaign 966)

Filed Jun 30, 2026 · Engine · MD

Driving home from work on [XXX] (not a safe location)when my car lost power and engine light began to flash. I pulled off to the side of road and called my dad. He came with a code reader and said there was a code P1326. He cleared the code and car drove normally again. 2 days later it began to run rough. I was told about the engine recall so I called Hyundai corporate and told them this same story. I was advised to take to dealership and have the “rod bearings inspected” and shouldn’t matter that my dad cleared the code. The dealership(Massey Hyundai MD) said it had a burnt valve and not part of warranty. But never checked rod bearings. When I called corporate. They said nothing they could do. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Jun 22, 2026 · Electrical, Engine · CA

My 2017 Hyundai Sonata SE, equipped with the Theta II 2.4L GDI engine, is experiencing severe powertrain failures including rhythmic metallic engine knocking, catastrophic oil consumption, and un-commanded surges/jumping in speed while driving. These symptoms manifested following an unauthorized engine replacement performed by Hyundai of El Cajon under Repair Order [XXX], where the dealer covertly outsourced my vehicle to a third-party shop (Legacy Motor Works) to install an unverified used salvage engine block rather than a certified factory assembly. This vehicle is a Class Vehicle under In re: Hyundai and Kia Engine Litigation (Case No. [XXX]), and the KSDS software update (Campaign 953) was successfully completed on my vehicle in 2019. The engine knock, surging, and oil consumption are consistent with the known connecting rod bearing failure defect described in the federal safety agency investigation PE17-007. The dealership is currently denying warranty coverage, citing a mileage limit that does not exist under my Lifetime Powertrain Warranty, and they are withholding physical documentation of the repair terms. The vehicle is also experiencing secondary safety failures, including a continuous airbag SRS warning light (two years) and electrical shorts caused by the salvage-yard alternator installation, which have destroyed 4 to 5 car batteries. This engine failure represents a significant safety hazard, as the vehicle periodically loses power and surges without driver input. I am requesting that the federal safety agency investigate this pattern of warranty denial, parts-sourcing fraud, and the safety risks posed by this substandard engine installation. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed May 27, 2026 · Engine · RI

The rod bearings failed in the engine. The vehicle is currently at the dealership and is available for inspection. Rod bearing failure can cause complete engine seizure while driving, creating a serious risk of losing vehicle control at any speed. This is a known issue with Hyundai's Theta II engine. Yes. The dealership performed a diagnostic on April 27, 2025 and confirmed rod bearing failure. Yes. The dealership inspected the vehicle and Hyundai corporate opened a warranty case and arranged the repair appointment, initially confirming coverage before later denying the claim without providing documentation. The dealership has also repeatedly failed to provide documentation supporting the denial of my warranty claim despite my requests beginning April 29, 2025. I have also been unable to get callbacks from the dealership after being promised updates on May 1st, May 7th, and after requesting a manager on May 18th. As of May 27, 2025 I have still not received any documentation or a callback. The check engine light came on prior to the failure. I proactively checked and changed the oil, added Lucas oil treatment, replaced the spark plugs, and replaced the battery attempting to diagnose and resolve the issue before bringing it to the dealership. No oil pressure warning light ever appeared. The check engine light persisted despite these efforts which is what led me to bring the vehicle in.

Filed May 7, 2026 · Engine · FL

Engine experienced severe metallic knocking and loss of power. A certified Hyundai technician confirmed a FAILED Bearing Clearance Test (RO #354331). Hyundai Motor America is refusing to honor the Engine II Class Action Settlement warranty, citing internal code A99 because the vehicle was purchased at an auction, even though the title is CLEAN. This pose a safety risk of engine seizure and potential fire.

Filed Mar 21, 2026 · Engine · TX

Care recently became inoperable. The engine was knocking, then stalling and then inoperable. Checked Hyundai website to find Engine Recall describing exactly what my Hyundai was/is experiencing. I brought vehicle to Clay Cooley dealership (39444 Lyndon B Johnson Fwy, 75232) and explained that I see the recall on the Hyundai website describing what my vehicle is experiencing. After their service mechanics review, the Service Department Representative falsely accusing me of the engine failure, stating that I "must not have changed my oil regularly". According to the service department, my 2017 Hyundai Sonata (132,000 miles) is not covered in the engine recall, and I must pay $4,926.53 for the repair. cc: FTC - ReportFraud.ftc.gov Texas Attorney General - Consumer-Protection/file-consumer-complaint

Filed Mar 13, 2026 · Engine · 95,000 miles · NY

The contact owns a 2017 Hyundai Sonata. The contact stated that while his wife was driving at an undisclosed speed, the vehicle experienced engine failure. The vehicle made a knocking sound prior to the failure. No warning lights were illuminated. The vehicle was towed to the residence and eventually towed to the dealer, but was not diagnosed or repaired. The dealer acknowledged the engine failure and that the failure was a common failure. The dealer declined the repair due to a lack of service records. The contact was offered a combustion cleaning; however, the vehicle was disabled. The manufacturer was notified of the failure. The approximate failure mileage was 95,000.

Filed Mar 6, 2026 · Engine · 132,000 miles · FL

The contact owns a 2017 Hyundai Sonata. The contact stated that the vehicle had experienced excessive oil consumption, caused by engine rod bearing failure. The engine rod bearing failure caused excessive oil consumption and premature spark plug fouling, requiring the frequent replacement of the spark plugs. The dealer was notified of the failure. The vehicle was not repaired. The manufacturer was notified of the failure. The failure mileage was approximately 132,000.

Filed Feb 8, 2026 · Engine · FL

My 2017 Hyundai Sonata Hybrid has a permanent and recurring DTC P1326 (Knock signal range/performance) from the Knock Sensor Detection System (KSDS), indicating potential connecting rod bearing wear in the Nu 2.0L engine. The vehicle enters limp mode (reduced power, limited acceleration/speed) on the highway under load, with hard engine vibration, tinkling/knocking noise from under hood, and significantly reduced MPG. These symptoms create a serious safety risk: sudden loss of power at highway speeds (e.g., 50+ mph) makes it difficult to maintain speed, merge, or avoid hazards, increasing crash risk or stranding in traffic. In rare cases, bearing wear can lead to engine seizure or failure. The problem first appeared summer 2024 at approximately 115,000 miles. The Check Engine Light illuminates (cristmass tree), and limp mode triggers during highway driving. I have an OBD scan showing confirmed, pending, and permanent P1326, plus related hybrid communication codes (U0293, U1004) likely secondary to the protection mode. The vehicle has been inspected multiple times (four visits) by a Hyundai dealer. Each time they scanned the code, performed basic checks, but stated “engine is working normal, no road vibration, nothing” and did not resolve the issue. The code returns immediately after clearing. I replaced the knock sensor, engine mounts, spark plugs, ignition coils myself—did not fix it. Dealers did not perform the full bearing clearance test or follow TSB 22-01-023H (Service Campaign T6G) procedure as required for this known issue (related to Recall 209 and Campaign 966). The component (engine/connecting rod bearings) is still in the vehicle and available for inspection. No police, insurance, or other parties have inspected it beyond the dealer. This matches a widespread known defect in 2011–2019 Sonata Hybrids (bearing wear triggering P1326/limp mode).

Filed Jan 24, 2026 · Engine · AZ

My 2017 Hyundai Sonata is exhibiting a severe metallic knocking noise and metal debris in the engine oil—primary indicators of the Theta II engine defect (the federal safety agency Campaign 17V578). These symptoms indicate imminent engine failure, posing a significant stall and crash risk. On or around 8/20/25, I took the vehicle to Earnhardt Hyundai-San Tan. I informed the technician of the oil burning and metal shavings. They refused to perform the recall repair and charged a $200 diagnostic fee for an inspection related to a federally mandated safety recall. Under federal law (49 U.S.C. Chapter 301), recall remedies must be provided at no cost to the owner. Furthermore, components were not reassembled correctly during the inspection. The vehicle is now leaking oil onto my driveway and has been rendered inoperable. It has not been driven since I picked it up on August 25, 2025. I am requesting that Hyundai be compelled to perform the recall remedy and reimburse the unauthorized diagnostic fee.

Filed Jan 19, 2026 · Engine · FL

The 2017 Hyundai Sonata has had an ongoing engine malfunction defect that is causing engine knocking, stalling, and smell and rapid depletion of oil. The continuous issues are concerning especially when the car is not driven on a regular basis as it is utilized as a second vehicle. This has been a noticeable issue for quite sometime now. I have taken the car to the Hyundai dealership on multiple occassions after notably heavy oil consumption in a short time period in between scheduled oil changes. I am told by the dealership that it is evident that the engine is rapidly processing and burning oil inappropriately from a possible manufacturing defect recall related to connecting-rod bearing failure that was issued by Hyundai for various Hyundai models. The damaged engine may stall, increasing the risk of a crash. In addition, oil may leak onto hot exhaust components, increasing the risk of fire.

Filed Nov 29, 2025 · Engine · FL

While driving my 2017 Hyundai Sonata, the engine suddenly began making a loud knocking noise and the vehicle entered "limp mode" The check engine light was blinking, I took the car to a very close autozone and the check engine light came on with code P1326 (pricture upload files), which is directly related to the known KSDS connecting rod bearing defect. This issue is part of Hyundai’s safety recalls and engine warranty extensions. After that, I called Hyundai directly (reference number for that call #XXX). A kind young woman informed me that my car had been through "Service Campaign 953" and successfully completed a "Knock Sensor Detection System (KSDS) Software Update." Thanks to this, she explained that my car is under the "Hyundai TXXI warranty" and that, given the noise I was hearing along with the "P1326" code, it was very likely that my car qualified for a free engine replacement. She then scheduled an appointment for me at the nearest Hyundai dealership for the following morning. After more than two weeks of inspection, the dealer confirmed that the engine has internal damage and needs a complete replacement due to rod bearing failure. This is the exact defect addressed in Hyundai’s safety campaigns. However, Hyundai Corporate is refusing to cover the engine replacement because the vehicle exceeded its mileage limit, even though the engine failure is clearly caused by the known safety-related defect. The dealer acknowledged the problem and documented everything, but Hyundai is denying proper safety recall-related coverage. This puts my safety and the safety of others at risk, the vehicle is currently disabled and undrivable at the dealership due to the defect. Hyundai is only offering a buyback or a small cash settlement instead of performing the necessary safety repair. I am filing this complaint for many reasons but mainly because the refusal to replace the defective engine, despite the recall-related code P1326 and confirmed bearing failure. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFOR