9.4

really awful
Crashes / Fires:
0 / 0
Injuries / Deaths:
0 / 0
Average Mileage:
1,186 miles

About These NHTSA Complaints:

This data is from the NHTSA — the US gov't agency tasked with vehicle safety. Complaints are spread across multiple & redundant categories, & are not organized by problem.

So how do you find out what problems are occurring? For this NHTSA complaint data, the only way is to read through the comments below. Any duplicates or errors? It's not us.

2021 Hyundai Sonata engine problems

engine problem

Find something helpful? Spread the word.
Get notified about new defects, investigations, recalls & lawsuits for the 2021 Hyundai Sonata:

Unsubscribe any time. We don't sell/share your email.

2021 Hyundai Sonata Owner Comments

problem #7

Mar 072023

Sonata

  • miles

A D V E R T I S E M E N T S

My 2021 Sonata has 32,000 miles & it broke down in the middle of the road. My safety & my daughters safety were at risk. We could have been hit or killed. There were no warning lights. It had to be towed. Repair shop reports the transmission is no good. This vehicle should not have transmission issues. Hyundai will not even cover a rental car. The dealership can-€™t even work on it for 1-2 weeks. I work & have kids. I need a vehicle. The car breaking down in the middle of the road with no warning is dangerous.

- Georgetown, DE, USA

problem #6

Dec 092022

Sonata 4-cyl

  • miles
Very loud car alarms sounded, e.g., it sounded like a something like a red alert in an old Star Trek episode. warning light indicated engine overheated, extreme exhaust/smoke bellowed out from rear of car while decelerating on highway exit ramp. My wife and I were inside the car during this event. This event happened on 5 pm EST December 9 at Hamilton Avenue exit on Ohio 126 Cross County Highway (Ronald Reagan Highway) in the Cincinnati metropolitan area. Had to park car within one mile. I had the car towed to the nearest dealer after it had cooled for 1 +hour. I was afraid the engine was going to explode or catch fire as I was decelerating. The dealer suggests the heat exchanger needed replacement. However, after 45 days, Hyundai has not shipped the heat exchanger that I have been made aware. I am concerned this event may be likely to reoccur and with resulting potential injuries to the occupants inside.

- Loveland, OH, USA

problem #5

Oct 172022

Sonata 4-cyl

  • miles
Oct 12: Engine stalled exiting I95 in Kittery Maine. Engine light flashed but did not stay on. Was able to get to safe place but car would not go more than 15mph. Hampton Huyndai reported mis-fire but stated it cleared on its own. Oct 17th: Engine stalled on highway ramp to I495, nearly causing me to be rear ended by other vehicles. Car would not go more than 15 mph. Engine light stayed on. Towed car to Key Salem Hyundai, defective injectors, warrantee repair. Oct 23rd: Car stalls on I93, was able to take immediate exit and turn engine off. Engine light flashed but did not stay on. Took car in to Salem dealership on Oct 24th, no code found. Oct 25th: Car stalls again on city street. Light stays on, Salem dealership replaces cat. convrtr between Oct 26th through Nov 4th. Nov 9th: Car stalls again on city street. Light stays on, currently in Salem dealership. This is a safety issue, in two cases already this car has nearly gotten me in an accident on the highway. I am seeking arbitration for replacement. I am scared to drive this vehicle. I will have a third invoice pending this next repair.

- Salem, NH, USA

problem #4

Aug 242021

Sonata

  • 2,700 miles

A D V E R T I S E M E N T S

The contact owns a 2021 Hyundai Sonata. The contact stated while driving 65 MPH and attempting to accelerate, the vehicle failed to respond with the check engine warning light illuminated. The contact also heard a knocking sound coming from the vehicle. The contact pulled over on the side of the road and turn off and restarted the vehicle and the vehicle started operating as designed. The vehicle was taken to the dealer and the contact was informed that the transmission and engine needed to be replaced. The manufacturer was contacted but offered no assistance. A case was filed. The failure mileage was 2,700.

- Little Rock, AR, USA

problem #3

Aug 262022

Sonata

  • miles
Unknown

- Morrisville, NC, USA

problem #2

Apr 062022

Sonata

  • miles
Since we purchased this brand new vehicle, we have had in the dealership service department at a minimum of 5 times for same issue. The vehicle accelerates while stopped at a light so we have to put it in neutral to keep it from accelerating. Once we take out of Neutral and release the break, the vehicle accelerates rapidly without stepping on the gas pedal. The computer system always comes on warning that we need to take to dealership because there are engine problems. Then it goes off and comes on again. We have contacted Hyundai to file a complaint and it has gone no where. We have taken it to Hyundai dealership in Tucson and they keep replacing parts per Hyundai manufacturer service tech reps. per same Egr codes. We are taking the vehicle to the dealership again today 9/22/22 because it started again around 9/1/22 and we have been waiting for a loaner car again from Dealership for same problems. Meawhile, being forced to drive it due to only owning 1vehicle. Hyundai Manufacturer has continued to have dealership change out parts and this keeps happening. The vehicle has just over 25K miles on it to date. The first time we had it in the dealership for this problem was on 4/6/22. We have almost rearended several vehicles and are scared to death to drive this vehicle. It is a safety hazard. We purchased the 2021 Sonata vehicle brand new on 11/24/21 along with the lifetime parts and labor warranty. It had 15 miles on it. We also traded our 2018 Hyundai ELantra. We paid off the 2021 Sonata completely in 2021. The total cost of this transaction was $34,294.74.We have also followed all the Maintenance requirements. It is urgent that this complaint is investigated as soon as possible and Hyundai Manufacturer take responsibility now before someone gets killed. The vehicle is obviously a dangerous manufactured vehicle.

- Tucson, AZ, USA

problem #1

Dec 022021

Sonata

  • 5,600 miles
The contact owns a 2021 Hyundai Sonata. The contact stated that while the vehicle was at an independent mechanic for an oil change, the mechanic diagnosed the vehicle with transmission fluid leaking from the engine. The mechanic informed the contact that the transmission fluid leakage was flammable. The dealer was made aware of the failure but informed the contact that they were backed up with other vehicles and could not diagnose the vehicle for approximately three weeks. The vehicle was not repaired. The manufacturer was made aware of the failure and a case was opened. The failure mileage was 5,600.

- Waco, TX, USA

Not what you are looking for?