2018 Hyundai Ioniq Hybrid problems

Filed Oct 31, 2026 · Brakes, Driver assistance · TX

I am reporting a potentially serious braking system safety defect involving a 2018 Hyundai Ioniq Hybrid with approximately 72,000 miles. The vehicle has experienced recurring, intermittent ABS warning lights that illuminate unexpectedly and then disappear without a predictable pattern. In addition to the warning lights, the brake pedal intermittently pulsates, vibrates, and pushes back against the driver's foot during normal braking on dry pavement. These symptoms occur under conditions where ABS activation would not ordinarily be expected, raising concerns about the reliability and proper operation of the braking system. The vehicle was inspected by an independent mechanic who identified the Integrated Brake Actuation Unit (IBAU) as the suspected source of the malfunction. The mechanic also advised that Hyundai has issued a technical service bulletin concerning this braking system component. No specific diagnostic trouble code was provided. The intermittent nature of this problem is particularly concerning because the warning light may disappear even though the underlying issue remains unresolved. The combination of unexpected brake pedal pulsation and intermittent ABS warnings creates a potential safety hazard, particularly during routine braking or situations requiring an immediate stop. I am concerned that a complete failure of the Integrated Brake Actuation Unit could result in reduced braking effectiveness, increased stopping distance, or loss of braking assistance, potentially causing a serious collision, injury, or death. I respectfully request that the federal safety agency investigate whether this condition represents a broader safety-related defect affecting 2018 Hyundai Ioniq Hybrid vehicles and determine whether a safety recall is warranted. The symptoms have occurred intermittently, and the suspected component failure has been identified by an independent mechanic.

Filed Nov 25, 2025 · Engine · CA

My 2018 Hyundai Ioniq Hybrid has a safety-critical transmission defect. The vehicle slips violently from 1st to 2nd gear, loses acceleration, and causes unpredictable hesitation. This creates a danger when merging onto highways or crossing intersections. Hyundai refused goodwill assistance, denied escalation, and directed me to BBB Auto Line, but BBB does not accept 2018 vehicles. This defect matches known DCT failures in Hyundai hybrid models and presents a significant safety risk, especially when transporting my two young children ( we lost mother during the childbirth .

Filed Nov 25, 2024 · Airbags · 85,000 miles · FL · crash · 2 injuries

The contact owned a 2018 Hyundai Ioniq Hybrid. The contact stated while driving 75 MPH with her aunt in the front passenger's side seat, another vehicle suddenly merged into the contact's lane, causing the passenger's side of the vehicle to crash into the driver's side of the other vehicle. The vehicle then veered into a ditch on the right side of the road. The air bags failed to deploy. There was no warning light illuminated. The contact and her aunt exited the vehicle through the rear doors because the front doors were blocked by the bushes. The contact sustained pain in the right knee and ankle. The contact's aunt sustained pain in the right knee. The ambulance transported both passengers to the hospital, where they were informed that no other injuries were found. A police report was filed, but the contact did not have the police report information available. The vehicle was towed and totaled by the insurance company. The dealer was notified of the failure. The manufacturer was notified of the failure and a case was opened; however, the case was later closed. The failure mileage was approximately 85,000.

Filed Oct 11, 2024 · Transmission · TX

The clutch failed and the clutch and I believe the clutch actuator had to be replaced. It was not available for inspection upon request. My safety and the risk of others were compromised by the constant jerking and sputtering, of the gears that took place during vehicle operation. My acceleration was laggy and at some points nearly unresponsive. The vehicle was inspected by service technicians. A warning light saying: Warning please check Hybrid Driving System, Do not drive vehicle was illuminated. Mid to late October 2023

Filed Apr 8, 2024 · Engine · CA

The car engine started to stall, the engine light came on and advised me to shut off engine then I pulled over and smoke immidiatley filled the cabin and outside the hood. My engine could have blown up. Had I not pulled over so quickly my car would have caught fire and I would have died. Yes the Hyundai Folsom inspected the car and listed issue was a hole in the engine block. They stated it was caused by premature wearing of the rod bearings and refused to repair. The ONLY warning happened within seconds of the car stalling and failing to accelerate before I pulled over. The first symptoms was a noise I couldne place 5 days prior. It was a mild knocking sound that was subtle.

Filed Aug 30, 2023 · Electrical, Steering · CA

My lcd screen constantly goes black. A couple times the steering wheel locked the wipers and washer fluid went off at the same time. I had to hit the brakes and power the car on and off to reset it while making a turn. When having my window motor replaced for the SECOND time my dash where the speed is at all when black while driving on the freeway. I had to pull over and restart the car. My paint and my clear coat is separating on my trunk. It looks white not oxidation just separating and white. My driver side door button to lock the car kept getting stuck and was locking and unlocking. this left the possibilities of my car getting stolen from the door lock and the window motor leaving my window half down. My safety and the safety of others is obviously at risk with the electrical malfunctions. My local dealership left my issue’s unresolved for currently FIVE months with little to no compensation. I guess the life of my family and everyone else on the road is only $420.

Filed Jan 31, 2022 · Transmission · MN

There is a defect with the transmission control module (TCM) and dual-clutch transmission (DCT). This defect prevents the car from properly accelerating from a stop. The defect manifests in the following ways when pressing the accelerator: unresponsive or sluggish acceleration, jerking, shuddering, failure to shift, stalling and complete loss of power. Typically, the TCM defect manifests in two ways: shuddering/delayed brake release, which has happened over 20 times and loss of power/engine revving out of gear which has occured three times. These issues are unpredictable, unrepeatable and dangerous. I usually experience them while waiting at stop lights in busy intersections. Delayed and unpredictable acceleration and shifting could cause a traffic accident. I've notified the dealership three times and had it serviced once by licensed Hyundai technicians at the same dealership. They couldn't replicate the issue and claimed they had never heard of the problem. There are no warning lights when this issue occurs and the dealship said there were no diagnostic codes indicating the problem. Defective TCM & DCT software is a known issue that resulted in a recall campaign for the 2016 Hyundai Tucson. This issue has been documented in the following vehicles: 2017 Hyundai Elantra Eco, 2017 Hyundai Sonata Eco, 2016 – 2017 Hyundai Tucson, 2016 Hyunda Veloster Turbo. Hyundai issued the following service bulletins informing dealerships about the TCU software issue specific to the Tucson: #5NP-X7J3D-10, TSB# 16-01-035, #5NP- S9D9P-10

Filed Dec 27, 2020 · 30 miles · CA

Vehicle battery is depleted and needs servicing or replacement.

Filed May 17, 2019 · Transmission · 18,300 miles · PA · crash

The car shifts from drive mode into sport mode by itself without the driver manually moving the gear shift from drive to sport. This happens randomly, but always when the car is in motion and always in a low gear( usually first gear ). It has happened both when making a turn and going straight ahead , usually when the car starts to move after being stopped like at a traffic light. I can get the car to go back into drive mode by physically moving the gearshift into sport mode and then back into drive mode again. Unfortunately, the most recent episode of this happened when I was pulling into my garage. I was halfway into the garage when the car switched to sport mode by itself. The car was still in motion instantly started moving faster and in seconds it hit the back wall of the garage.

Filed Jan 9, 2019 · Electrical, Engine · 4,300 miles · FL

It began shortly after I purchased the car in feb 2018 with the A/C working only intermittently and the settings on the cluster having the same problem, and this electrical problem escalated into a safety issue when on dec 6 the rke failed (battery on fob strong) and a re-start on car did not work, until the spare key was tried. Since dealer found no problem with either key, the safety issue remains a major concern for the senior citizen owner who might get caught again without access to the car and with a non-functioning engine. The electrical problem shows itself intermittently in unprovoked beeps of the passenger door, as well as in the cluster settings.