Hyundai reprogramed their Theta engines to prevent an ongoing problem related to Theta engines not receiving oil to the crankshaft and connecting rod bearings. The software modification was done by an unknown software house. When I got the first notice, I asked both the local dealer, and the official Hyundai site if this software would cut power, potentially at the wrong time, like going up an entrance ramp. I got no response and I found out why. I tried entering a highway where traffic was at 75 mph. When I got onto the ramp the car was running fine. Suddenly the power just went away. I had the gas pedal all the way to the floor and watched the tachometer and speedometer go down rather than up. I pulled off at the next exit and switched the programming on my transmission to normal from econ mode. Up the ramp I went, and car started slowing down. Tried one more time using the sport mode and the power went away. I'm afraid to try and run on a freeway at rush our because of the lack of power. I think the needs to be a review of the software and see if changes can be made.

- Madison, WI, USA

Car engine light turns on indicating connecting rod bearing failure. Vehicle has stopped running properly while driving at high speeds & caused safety concerns. Issue has shown to be consistent across many other Hyundai vehicles. Issue has not yet been checked by manufacturer but is available for future inspection.

- Atlanta, GA, USA

The Camshaft Seals are defective and cause the engine light to come on and also I experience power loss while driving on the highway.

- Wilkes Barre, PA, USA

Vehicle info: 2015 Sonata Se. 97450 Mileage. As with most all complaints with this engine, it is deteriorating slowly as the knock sensor code P1326 has sensed a knock. A private mechanic has verified that a rod bearing is either bent or broken and knocking against the engine. This is after two Hyundai dealers have denied even inspecting my vehicle. Due to the title status of my vehicle (rebuilt title) Hyundai dealers (King Hyundai in Deerfield Beach, FL and Coconut Creek Hyundai in Coconut Creek, FL) are denying repairs because the engine has no active campaigns or recalls on the engine even though Hyundai Motors of America has extended the warranty to a lifetime duration for this exact issue. This is a huge liability situation as these engines are known to catch fire for this very issue and Hyundai/Kia has been fined $140 Million for not acting sooner on this matter. These vehicles have been known to catch fire inside the dealership service center while going through diagnostic testing by certified mechanics. I have had the Campaign 953 serviced in 2018, which was a software update to alert owners when the engine is already failing (sensing a bearing rod broken). This campaign did not address the faulty engine but only alert you. Hyundai Motor America has told me that a Hyundai dealership should not deny me warranty coverage however every dealership in Palm Beach and Broward counties are denying my service order approval. Service managers refuse to send in a pre-authorization to Hyundai Motor America despite corporates approval of this warranty coverage therefore nobody wants to take responsibility nor liability for a known safety defect in Hyundai engines.

- Delray Beach, FL, USA

The contact owns a 2015 Hyundai Sonata. The contact stated the vehicle was hard to start. After the vehicle was started, the started shaking abnormally. The check engine and ABS warning lights were illuminated. The vehicle was taken to an independent mechanic who informed the contact about the engine combustion. The vehicle was towed to the local dealer where it was diagnosed that oil was leaking onto the spark plugs. The vehicle was not repaired. The manufacturer was notified of the failure however, no further assistance was provided. The approximate failure mileage was 124,000.

- Hinesville, GA, USA

The contact owns a 2015 Hyundai Sonata. The contact stated that the vehicle was consuming an excessive amount of engine oil. Upon inspection, the contact noticed there was no oil on the dipstick. The vehicle was taken to the independent mechanic and diagnosed that there was no oil in the oil reservoir. The mechanic added four quarts of oil to the oil reservoir and referred the contact to the dealer. The dealer was made aware of the failure and scheduled an upcoming appointment for an oil consumption test. The vehicle was not repaired. The manufacturer was made aware of the failure and a case was opened. The failure mileage was approximately 113,000.

- Graham, NC, USA

Driving my sonata in town 40 miles per hour got to a light and check engine light started flashing I pulled over and parked it in an advanced auto parking lot parts man come out put scanner in car and read code p00137 knock sensor so I had it towed to home due to I called hyundai and mechanic said it would be around the 16th before he could look at it. I tried to start cat again and would not crank I went on line and jumped car from relay and motor is seized up. Have about 135,000 miles roughly and now looking into problem car drinks oil like fierce and now motor is bad

- Havelock, NC, USA

Out of the blue, I heard a very loud knocking noise coming from my engine. I was driving my children to school and as I hit the gas pedal the less power my car had. Not only would it not accelerate much but even the lights would dim. I am now paying over $400 a month for a car that I can not drive and walking where I need to go. My vin number does not qualify me for the engine recall Hyundai has, even though my car is the right year, make and model, engine size and problem that the recall is for. Awesome right?

- Urbana , OH, USA

The car caught fire. I only had the car for 3 weeks. I had just started the car for work. There were no warning lights on. If some unknown guy have not told me to get out my car i would had died.

- Not Hispanic, OH, USA

While traveling on the interstate, the car started shuddering. Pulled off and went to auto part store and they read the code #4 misfire. Took car to my mechanic and he said #4 cylinder was dead. Proceeded to take car to dealership and they said #4 cylinder had burn valve with hole in valve. We hey gave a quote for engine replacement. Took car back to my mechanic and he replaced engine at a cost of $5466.28. The replacement engine was a 2014 with 13k miles. The car only had 107186 miles at time of incident.

- Hazel Green , AL, USA

Check engine light on. Taken to hyundai dealership for recall repairs. At the time, 3 recalls on vehicle. Informed that check engine light was on due to recalls. Dealership kept car for 1? weeks and notified me that 1 recall (filter) was not completed because parts are on back order. Dealership had me pick up vehicle and said that it is okay to drive car; however, after calling another Dealership, the Service rep informed me that cars should not be driven while engine filter recalls are open because it could potentially further damage vehicle. Vehicle has now been sitting in my garage for over 2 months and I'm making payments for a car I cannot drive.

- Bakersfield, CA, USA

The connecting-rod bearings in the engine damaged. I've read that it was a recall problem in hyundai's engines. i have abnormal knocking noises from the engine, reduced power or hesitation, illumination of the "check engine" light.

- Detroit, Mi, Usa, MI, USA

The contact owns a 2015 Hyundai Sonata. The contact stated while driving approximately 75 MPH, the vehicle began to vibrate violently. The contact pulled over and had the vehicle towed to a local dealer where it was diagnosed with needing a new transmission. The contact stated that the check engine warning light was illuminated. The manufacturer was not informed of the failure. The failure mileage was approximately 124,000.

- Greenacres, FL, USA

My vehicle started losing oil between oil changes. Not leaking on the ground. I looked it up and found out this is a very common issue. Just my luck. My vehicle now has major engine issues. Knocking in the engine, shaking. I looked it up and to not my surprise, very common. My vehicle is available for inspection. Safety wise I was traveling 70 on the interstate and the engine just quit and decelerated very quickly with cars driving by fast. I am getting the vehicle checked inspected Monday 11/29 I had it towed to a garage. I will also contact the local Hyundai dealer. No warnings lamps prior to incident

- Fort Wayne, IN, USA

Hello, I took my car to my closest dealership Brandon Hyndai, because my car stop working properly. The car engine warning light came on followed by a knocking noise, when I try to accelerate, it reduce the power, it smells like burn.It-??s been 3 weeks since my car has been sitting at the Brandon Hyundai dealership parking lot without a full diagnostic, the only thing they have told me it-??s that it gave them the P1326 code that it-??s engine related, but they needed to run more test before starting an engine replacement submission due to a recall.My car only has 69000 miles.I have been checking almost daily to see if they have done something but so far, they haven-??t. They also didn-??t provided me with a lender car, because they didn-??t have one or so they say. I have waited patiently, but 3 weeks it-??s too long for a diagnosis and I have been taking a bus to work because I cannot afford to rent a car, that the dealer is not even 100 percent certain if I will be reimbursed for it. It-??s been an stressful 3 weeks and it seem this issue is not being taken serious, plus they also want to charge me 300 dollars for them to start the engine replacement submission, which I he agreed to as I don-??t seem to have another choice. I am desperate, because I am not sure what will happen next. I had to call corporate and started a case with them, but it can take up to a week or more for them to contact me. The worst part is not knowing and there is no much information about it.And the coworkers at the dealership are not being helpful at all, I am not sure if because they don-??t have much knowledge about it or they really don-??t care about the customers.

- Seffner , FL, USA

I was driving at 55 mph and vehicle stall and cut off pulled side the road tried to crank back up and nothing happened. after each oil change no oil show on stick and also when i get an oil change they tell me barely any oil in vehicle. this has happened every since i purchased the veh on Dec 10 2019

- Minden, LA, USA

Check Engine Light began flashing and Oil Pressure Light illuminated while operating vehicle under normal conditions on the interstate. Vehicle was pulled over and towed to local Hyundai dealership. The dealership states the engine has failed.

- Forest Hill, MD, USA

Engine started knocking out of nowhere took it to the dealership to see if I had a recall was told that I needed to replace engine which would cost between 8k-10k. The recalls for engines on Hyundai sonatas were for 2011-2013 and 2016. Not really understanding how they skip a year with everyone with this year. I don-??t have the money to replace engine

- Augusta , GA, USA

My car is burning through a quart of oil appx every 600 miles- this is NOT normal it's excessive oil consumption.

- St. Petersburg, FL, USA

while driving about 6/7 lights on the dash comes on and the car stops. This happened several times and I took it to my auto mechanic Christian Brothers at Dacula, Ga. They said it is a soft ware problem and Hyundai USA does not accepts their are any software malfunction problems. Sometimes the car would start back again and other times it will not. Therefore I had to tow my car twice to the garage to have them check it out and fix it. [XXX] INFORMATION Redacted PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6).

- Dacula, GA, USA