FaultScore

FaultScore report

2018 Hyundai Ioniq Hybrid problems

Owners have filed 18 complaints about the 2018 Hyundai Ioniq Hybrid with NHTSA between 2018 and 2025. The largest single group is the engine & cooling. Across this model's run it ranks 5 of 6 worst.

C

FaultScore 59/100

Higher is worse. Measured against the other years of the Hyundai Ioniq Hybrid.

How this is worked out

The numbers

18

Complaints

2

Crashes reported

0

Fires reported

1

Injuries reported

3,000 mi

Median mileage at failure

Half of reported failures happened before this

91%

Failed under 36,000 miles

Inside a typical bumper-to-bumper warranty

What kind of bad

The letter says how bad. This says what kind — whether this year drew an unusual number of complaints, unusually dangerous ones, or failures that arrived unusually early.

Complaint volume 27 vs 50 Severity 86 vs 50 Early failure 100 vs 50
The dashed ring is 50 — the national norm. Further out is worse.
Complaint volume — 27
Against the median year of the Hyundai Ioniq Hybrid. 50 means typical for this model; 100 means roughly double.
Severity — 86
16.7% of these complaints involved a crash, fire, injury or death, against a national rate of 9.7%.
Early failure — 100
91% of failures with a mileage on record happened under 36,000 miles, against a national rate of 29%.

How 2018 compares with every other Hyundai Ioniq Hybrid

Click any bar to open that year's report.

Complaints filed with NHTSA, by model year. Bar colour is the FaultScore grade: A B C D F ungraded

What breaks on a 2018 Hyundai Ioniq Hybrid

Every complaint is filed against a part. Follow any row for the complaints about that part alone.

Other & Unspecified 3 16.7%

Median failure at 1,000 miles

Electrical System 3 16.7%

Median failure at 2,650 miles

Transmission & Drivetrain 3 16.7%

1 crashes, 0 fires · median 18,300 mi

Engine & Cooling 3 16.7%

Median failure at 4,300 miles

Acceleration & Cruise Control 2 11.1%

Median failure at 350 miles

Windows, Mirrors & Wipers 1 5.6%
Brakes 1 5.6%

Median failure at 3,000 miles

Steering 1 5.6%
Airbags 1 5.6%

1 crashes, 0 fires · median 85,000 mi

When it fails

Odometer readings owners gave when they filed. About half of all complaints include one.

Under 1,000 miles 3 27.3%
1,000 – 9,999 miles 6 54.5%
10,000 – 24,999 miles 1 9.1%
75,000 – 99,999 miles 1 9.1%

When owners complained

A spike years after the car went on sale usually means a part wearing out on schedule across the whole fleet — the kind of pattern no single owner can see from inside their own car.

Jan 2018 peak 3 Nov 2025

NHTSA investigations into the 2018 Hyundai Ioniq Hybrid

An investigation is the step before a recall: the agency has seen enough complaints to look into a pattern itself. An open one means it thinks something may be wrong and nothing has been fixed yet.

DP22005 Opened 27 Jan 2023 Closed 7 Aug 2023 ELECTRICAL SYSTEM:PROPULSION SYSTEM

Pedestrian alert sounds

NHTSA 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 NHTSA.gov 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 Marc...

Complaints that involved harm

Reports where the owner recorded a crash, a fire, an injury or a death.

at 85,000 miles Milton, FL Crash 2 injured

AIR BAGS

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.

NHTSA complaint #11627337 — an unverified report by a vehicle owner.

at 18,300 miles Pennsburg, PA Crash

POWER TRAIN

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.

NHTSA complaint #11208212 — an unverified report by a vehicle owner.

The most recent complaints

In the owners' own words, exactly as filed with NHTSA.

Los Angeles, CA

ENGINE

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 .

NHTSA complaint #11701382 — an unverified report by a vehicle owner.

at 85,000 miles Milton, FL Crash 2 injured

AIR BAGS

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.

NHTSA complaint #11627337 — an unverified report by a vehicle owner.

Meadows Place, TX

POWER TRAIN

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

NHTSA complaint #11619309 — an unverified report by a vehicle owner.

South Lake Tahoe, CA

ENGINE

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.

NHTSA complaint #11581760 — an unverified report by a vehicle owner.

El Centro, CA

STEERING

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.

NHTSA complaint #11541573 — an unverified report by a vehicle owner.

El Centro, CA

ELECTRICAL SYSTEM

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.

NHTSA complaint #11541573 — an unverified report by a vehicle owner.

El Centro, CA

VISIBILITY/WIPER

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.

NHTSA complaint #11541573 — an unverified report by a vehicle owner.

Minneapolis, MN

POWER TRAIN

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

NHTSA complaint #11449635 — an unverified report by a vehicle owner.

at 30 miles Fremont, CA

UNKNOWN OR OTHER

VEHICLE BATTERY IS DEPLETED AND NEEDS SERVICING OR REPLACEMENT.

NHTSA complaint #11385093 — an unverified report by a vehicle owner.

at 18,300 miles Pennsburg, PA Crash

POWER TRAIN

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.

NHTSA complaint #11208212 — an unverified report by a vehicle owner.

at 4,300 miles Miami, FL

ELECTRICAL SYSTEM

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.

NHTSA complaint #11166040 — an unverified report by a vehicle owner.

at 4,300 miles Miami, FL

ENGINE

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.

NHTSA complaint #11166040 — an unverified report by a vehicle owner.

at 1,000 miles Harmony, PA

UNKNOWN OR OTHER

MANY ISSUES: 1. GETS STUCK IN PARK. 2. BACK UP CAMERA FUZZY EVEN AFTER CLEANED. 3. APPLE CAR PLAY DROPS OUT. AND OR SWITCHES FROM TO CURRENT PHONE CALL. 4. TIRE PRESSURE SYSTEM IS MESSED UP. THE TIRES SYSTEM DOESN'T TELL YOU WHEN THE TIRES ARE BELOW 30LBS. THESE ARE JUST A FEW ISSUES.

NHTSA complaint #11153450 — an unverified report by a vehicle owner.

at 1,000 miles Harmony, PA

ELECTRICAL SYSTEM

MANY ISSUES: 1. GETS STUCK IN PARK. 2. BACK UP CAMERA FUZZY EVEN AFTER CLEANED. 3. APPLE CAR PLAY DROPS OUT. AND OR SWITCHES FROM TO CURRENT PHONE CALL. 4. TIRE PRESSURE SYSTEM IS MESSED UP. THE TIRES SYSTEM DOESN'T TELL YOU WHEN THE TIRES ARE BELOW 30LBS. THESE ARE JUST A FEW ISSUES.

NHTSA complaint #11153450 — an unverified report by a vehicle owner.

at 3,000 miles Milford, OH

UNKNOWN OR OTHER

CLICKING NOISE COMING FROM THE BOTTOM OF THE ENGINE EVERY TIME THE BRAKE PEDAL IS DEPRESSED. SOMETIMES THE CLICKING NOISE WILL CONTINUE AFTER THE CAR HAS BEEN PARKED AND LOCKED. THE FIRST TIME THE CLICKING STARTED, I PARKED MY CAR AND A WARNING "CHECK BRAKE SYSTEM" APPEARED BRIEFLY IN MY DASHBOARD DISPLAY BUT THE CLICKING PERSISTED. THE PEDAL FELT SLUGGISH WITH NOT MUCH RESISTANCE.

NHTSA complaint #11141250 — an unverified report by a vehicle owner.

at 3,000 miles Milford, OH

SERVICE BRAKES

CLICKING NOISE COMING FROM THE BOTTOM OF THE ENGINE EVERY TIME THE BRAKE PEDAL IS DEPRESSED. SOMETIMES THE CLICKING NOISE WILL CONTINUE AFTER THE CAR HAS BEEN PARKED AND LOCKED. THE FIRST TIME THE CLICKING STARTED, I PARKED MY CAR AND A WARNING "CHECK BRAKE SYSTEM" APPEARED BRIEFLY IN MY DASHBOARD DISPLAY BUT THE CLICKING PERSISTED. THE PEDAL FELT SLUGGISH WITH NOT MUCH RESISTANCE.

NHTSA complaint #11141250 — an unverified report by a vehicle owner.

at 500 miles York, PA

VEHICLE SPEED CONTROL

WHILE DRIVING THIS MORNING (SMART CRUISE CONTROL DISABLED BY THE WEATHER), I SET THE CRUISE CONTROL AND EVERYTHING WAS WORKING OK. I CANCELLED DUE TO TRAFFIC AND REENGAGED WITHOUT ISSUE. WHEN I REQUESTED ADDITIONAL SPEED WITH THE INCREASE CONTROL, THE CAR ACCELERATED AND CONTINUED TO ACCELERATE AND DID NOT STOP ACCELERATING UNTIL I HIT THE BRAKES AND CANCELLED THE CRUISE CONTROL. THIS IS VERY UNSAFE. I EXPECT THIS FIXED AND WILL CONTACT THE NHTSA AND ALSO FILE A COMPLAINT WITH THEM. THIS IS DANGEROUS AND IT IS ONLY DUE TO MY ABILITY TO QUICKLY REACT DID I AVERT AN ACCIDENT IN SNOWY CONDITIONS! ***** I AM CHECKING THE NO CRASH BUTTON ONLY BECAUSE MY QUICK ACTION AND RESPONSE AVERTED AN ACCIDENT, BUT THIS IS VERY DANGEROUS! *****

NHTSA complaint #11102586 — an unverified report by a vehicle owner.

at 200 miles Carlisle, PA

VEHICLE SPEED CONTROL

I AM VERY CONCERNED ABOUT THE CRUISE CONTROL. WHILE DRIVING THIS MORNING (SMART CRUISE CONTROL DISABLED BY THE WEATHER), I SET THE CRUISE CONTROL AND EVERYTHING WAS WORKING OK. I CANCELLED DUE TO TRAFFIC AND REENGAGED WITHOUT ISSUE. WHEN I REQUESTED ADDITIONAL SPEED WITH THE INCREASE CONTROL, THE CAR ACCELERATED AND CONTINUED TO ACCELERATE AND DID NOT STOP ACCELERATING UNTIL I HIT THE BRAKES AND CANCELLED THE CRUISE CONTROL. THIS IS VERY UNSAFE. I EXPECT THIS FIXED AND WILL CONTACT THE NHTSA AND ALSO FILE A COMPLAINT WITH THEM. THIS IS DANGEROUS AND IT IS ONLY DUE TO MY ABILITY TO QUICKLY REACT DID I AVERT AN ACCIDENT IN SNOWY CONDITIONS! -SCOTT

NHTSA complaint #11065792 — an unverified report by a vehicle owner.