The worst 2018 Hyundai Sonata Plug-In Hybrid problems
Ranked by number of owner complaints. Mileage and cost come from what owners wrote.
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Recalls 1
Hybrid propulsion system
- What is wrong
- Hyundai Motor America (Hyundai) is recalling certain 2016-2018 Hyundai Sonata Plug-In Hybrid vehicles. These vehicles are equipped with a Voltage Protection Device (VPD), designed to protect the high voltage battery module, that may activate inadvertently.
- Risk
- If the VPD activates while the vehicle is being operated in Electric Vehicle (EV) mode, there may be a loss of power, increasing the risk of a crash.
- Remedy
- Hyundai will notify owners, and dealers will remove the VPD switch and install a new Battery Management System (BMS) that contains an Overvoltage Protection Device (OPD). The recall is expected to begin May 2018. Owners may contact Hyundai customer service at 1‑855‑371‑9460. Hyundai's number for this recall is 175.
Recall number 18V166000 · Recall details
See all 1 recalls for the 2018 Hyundai Sonata Plug-In Hybrid
Defect investigations
Pedestrian alert sounds
the federal safety agency received a petition on or about July 18, 2022, requesting that Federal Motor Vehicle Safety Standard (FMVSS) 141 be applied to all electric and hybrid vehicles operating in the United States. The petition can be reviewed at under ODI Number 11486072. FMVSS 141 establishes performance requirements for pedestrian alert sounds for motor vehicles. The standard applies to hybrid and electric vehicles that have a gross vehicle weight rating of 4,536 KG or less or are defined as low-speed vehicles. The standard became fully applicable to all such vehicles manufactured on or after March 1, 2021.On January 27, 2023, the federal safety agency opened Defect Petition (DP) 22-005 to evaluate the subject matter described in the petition. On June 24, 2023 and as supplemented on June 25, 2023, the petitioner notified the federal safety agency he was withdrawing his petition. The petitioner indicated that, based on his review of data, there is no justification for asserting potential benefits that could be derived from actions sought by my petition. Based on the petitioner's withdrawal, DP22-005 is closed. Closure of this DP does not represent a determination by the federal safety agency regarding the subject matter of the petition.
DP22005
Loss of Motive Power
the federal safety agency received a letter dated July 13, 2022, petitioning the Agency to initiate a safety defect investigation into loss of motive power allegations attributed to oil drain pan assembly failures on certain Hyundai Motor America, Inc. and Kia America, Inc. vehicles spanning Model Years (MY) 2005-2021. The Petitioners cited examples of complaints indicating that the subject vehicles were experiencing rapid loss of engine oil due to oil drain plug back outs, resulting in loss of motive power and/or catastrophic engine damage. Additional complaints were provided which alleged that the oil drain pans lack sufficient structural integrity and are susceptible to cracking. The petition itself can be reviewed at under ODI number 11481745. On September 12, 2022, the Office of Defects Investigation (ODI) opened Defect Petition (DP22-003) to evaluate the Petitionersâ request. The Petitioners have provided additional complaints within four supplemental letters dated January 31, 2023, March 21, 2023, May 23, 2023, and August 4, 2023. ODIâs evaluation included the review and analysis of the complaints and supporting information submitted by the Petitioners, as well as additional complaints submitted directly to the federal safety agency which referenced either the oil drain plug or a crack in the oil pan. After reviewing the available data, ODI has not identified evidence that would support opening a defect investigation into the oil drain pan assemblies of the subject vehicles. Based on a review of the available information, a loss of motive power resulting from an oil drain plug back out has not occurred between the initial sale of a vehicle and the completion of its first oil change. If during an oil change service, a technician fails to remove the existing drain plug gasket before installing a new gasket, it is likely that a proper seal between the drain plug and the oil pan will not be made. An improper seal between the drain plug and oil pan could lead to the backing out on the drain plug, resulting in the sudden loss of oil while driving. Additionally, the provided examples of oil pan cracks were localized to the immediate vicinity of the oil drain plug and/or appeared to be the result of direct-contact with a tool during servicing. Â There is no information to support that a vehicle-based defect exists relating to the oil pan assembly, and instead the documented incidents are related to the failure to follow the proper maintenance procedures during oil change service. In October 2023, Hyundai published a Technical Service Bulletin (TSB) that provided detailed instructions for oil change service on its gasoline powered vehicles, specifically highlighting the need to remove and replace the existing drain plug gasket prior to reinstalling the drain plug. After a thorough review of the material submitted by the petitioner, the information already in the federal safety agency's possession, and the potential risks to motor vehicle safety implicated by the petitioners' allegations, the federal safety agency does not believe that a formal investigation is warranted. Therefore, the petition is denied. A Federal Register Notice (FRN) further detailing the federal safety agencyâs reasons for denial of the petition will be published. The reference numbers for the complaints to the federal safety agency cited by the petitioner can be found in the petition submission documents in the public file for DP22-003. To review those complaints and the additional complaints ODI added to its evaluation which are cited in the Closing Resume ODI Report Identification Number document, go to
DP22003
Technical service bulletins for the 2018 Hyundai Sonata Plug-In Hybrid 72
Bulletins tell dealers how to fix known problems. A warranty extension means the manufacturer pays for that repair for longer.
- This TSB references the Op codes to use for claim submission and the Parts required based on the vehicle’s...
- This TSB references the Op codes to use for claim submission and the Parts required based on the vehicle’s...
- Higher-than-expected engine oil consumption
- Higher-than-expected engine oil consumption
- The federal safety agency has issued an urgent safety advisory regarding dangerous, counterfeit...
- The federal safety agency has identified the presence of substandard and dangerous driver’s-side airbag...
- This bulletin provides information regarding condensation related to the accumulated moisture in the...
- Loss of connectivity or interruptions in the middle of using Bluelink Service functions
- This bulletin contains information about the proper removal of the windshield wiper blade protective cover...
- This bulletin provides important checkpoint guidelines when performing engine oil and filter change services.
See all 72 bulletins for the 2018 Hyundai Sonata Plug-In Hybrid
Compare the 2018 Hyundai Sonata Plug-In Hybrid
Other model years
Questions about the 2018 Hyundai Sonata Plug-In Hybrid
Is the 2018 Hyundai Sonata Plug-In Hybrid reliable?
Owners have filed 0 complaints about the 2018 Hyundai Sonata Plug-In Hybrid.
What is the most common problem with the 2018 Hyundai Sonata Plug-In Hybrid?
There are not enough complaints to tell.
How many recalls does the 2018 Hyundai Sonata Plug-In Hybrid have?
1 recall, covering hybrid propulsion system.
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