2017 Hyundai Sonata PLUG-IN Hybrid

On August 31st 2021, While driving my 2017 Hyundai Sonata PHEV on interstate 95 the check engine and hybrid system warning lights came on and the car simultaneously lost power for 3-4 seconds, which caused a decrease in speed from 65 to approximately 50 mph. There was a tractor trailer behind me but thankfully it braked to avoid striking my car. The car regained partial power and I was able to drive it home. I took the car to the dealership to have it repaired. The dealer diagnosed a faulty battery management system, and replaced this component after 17 days. On September 25, while driving on a street the car once again lost power for 3-4 seconds, with the check engine and hybrid system lights simultaneously illuminated. There was a recall on my vehicle several years ago to prevent this dangerous problem. I had the car repaired at that time but clearly the problem was not fixed as my car has subsequently lost power on two separate occasions, in a manner that could have easily caused a crash.

TL* THE CONTACT OWNS A 2017 HYUNDAI SONATA PLUGIN HYBRID. THE CONTACT STATED WHILE DRIVING 50 MPH, SHE HEARD AN ABNORMAL SOUND. THE CONTACT STATED THAT THERE WAS NO WARNING LIGHT ILLUMINATED. THE CONTACT DROVE TO HER RESIDENCE. THE CONTACT STATED SHE HAD THE VEHICLE TOWED TO HARRISONBURG FORD, INC. (3155 S MAIN ST, HARRISONBURG, VA 22801; (540) 434-0700), WHERE IT WAS DIAGNOSED WITH NEEDING THE ENGINE TO BE REPLACED. THE VEHICLE WAS REPAIRED. THE MANUFACTURER HAD NOT BEEN INFORMED OF FAILURE. THE FAILURE MILEAGE WAS APPROXIMATELY 75,000.*DT

I WAS DRIVING MY HYUNDAI 2017 SONATA PLUGIN HYBRID ON THE HIGH WAY IN HEV MODE AND SUDDENLY I FELT SEVERE VIBRATION IN MY CAR. THEN I CHANGED MY ENGINE TO EV MODE AND IT WAS FINE. ENGINE LIGHT CAME ON. EVERY TIME THE GAS ENGINE CAME ON THE CAR STARTED VIBRATING AND NON RESPONSIVE TO GAS. I DROVE ABOUT 10 MORE KM TOWARDS HOME ON ELECTRIC ONLY ENGINE AND THEN GOT IT TOWED TO THE DEALERSHIP. IT FELT LIKE ENGINE LOST ITS POWER. I RECENTLY CHANGED THE VOLTAGE PROTECTION DEVICE ON THE CAR AS A RECALL. ALL SERVICES WERE DONE ON TIME AND CAR HAD ONLY 33000 KM.

THIS IS MY FIRST TIME BUYING A BRAND NEW CAR IN MY MID 40'S. I PURCHASED THE CAR (PLUG IN HYBRID) WITH ONLY 25 MILES ON MARCH 15, 2018 AND AFTER 7 DAYS AND 353 MILES LATER, UPON DRIVING AND COMING TO A STOP IN THE CITY OF PHILADELPHIA, PA, THE CAR STALLED AND LOST POWER. WARNING MESSAGE "CHECK HYBRID SYSTEM." I HAD TO STEP ON THE GAS PEDAL ALL THE WAY DOWN TO THE FLOOR AND WAITED A SECOND OR TWO IN ORDER FOR IT TO MOVE AT A TURTLE'S PACE. FORTUNATELY, I WAS ABLE TO FIND A SAFE SPOT TO PARK THE CAR. IT WAS TOWED TO A LOCAL HYUNDAI DEALERSHIP NEAR ME AND AS OF YESTERDAY, 3/27, NO DIAGNOSTIC FINDINGS. I HAVE NOTIFIED HYUNDAI MOTOR AMERICA AND THEY HAVE OPENED A CASE#. I HAVE ALSO REACHED OUT TO THE SELLING DEALER TO HELP ME WITH THIS MATTER. THIS IS EXTREMELY UPSETTING AND DISAPPOINTING, ESPECIALLY FOR ME AS NEW CAR BUYER!!!

14 MARCH 2018 10:30 AM, 70 MPH ON US 101 TO SAN FRANCISCO, HEV MODE, RAINY WEATHER, 4 PASSENGERS FOR A BUSINESS MEETING. CAR STEERING SHUDDERED AS IF THE TIRES SLIPPED AND SPUN ON THE WET PAVEMENT. ESC, BRAKE, AND AUTO HOLD LIGHTS TURNED YELLOW. WAS ABLE TO DRIVE THE CAR NORMALLY TO REACH DESTINATION, PARKED, ATTENDED MEETING, AND STARTED DRIVING BACK HOME WITH MY PASSENGERS AT 3PM. ESC, BRAKE, AND AUTO HOLD LIGHTS WERE STILL ON. HEV MODE. 30 MINUTES LATER, I-280 AT 65+ MPH, ENGINE POWER DRASTICALLY REDUCED ABRUPTLY, CAR STARTED TO SLOW DOWN AND BECAME UNRESPONSIVE TO THE GAS. TURNED ON EMERGENCY FLASHERS AND WITH GREAT DIFFICULTY IN THE EVENING RUSH HOUR COMMUTE TRAFFIC, MANAGED TO SHIFT RIGHT THREE LANES AND TAKE THE NEXT EXIT, WENT INTO A PARKING LOT AND STOPPED THE CAR. CONSULTED MANUAL FOR ANY MEANINGFUL ACTIONS. STARTED CAR BACK UP. MIL LIGHT ALSO CAME ON ALONG WITH MESSAGE TO TAKE CAR TO DEALER. RAN VEHICLE DIAGNOSTICS AND GOT 'A POSSIBLE CONDITION WITH THE ECS HAS BEEN DETECTED AND A FULL SYSTEM CHECK IS RECOMMENDED SOON'. STARTED DRIVING CAR AGAIN. SAME LACK OF ENGINE POWER. DROVE THROUGH LOCAL ROADS AND COUNTLESS MANY TRAFFIC LIGHTS AND REACHED HOME AFTER 4 HOURS (NORMAL = 1 1/2 HOURS). AT HOME, PLUGGED CAR IN FOR CHARGING. CHARGING STARTED NORMALLY. AROUND 10PM, WANTED TO TAKE A PICTURE OF ALL THE LIGHTS, SO PULLED CHARGING CABLE OUT AND STARTED CAR. ALL LIGHTS WERE OFF EXCEPT MIL! DECIDED TO TEST DRIVE AND FOUND NO LOSS OF POWER. TOOK IT TO NEARBY FREEWAY, FLOORED GAS PEDAL. CAR RESPONDED WITH FULL POWER! NEXT DAY MORNING, DRIVING CAR TO DEALER, HEV LIGHT AND CONTINUOUS WARNING BEEP CAME ON, JUST A MILE AWAY FROM HOME.

ON 3/15/2017 AROUND 8AM, I STARTED MY CAR TO LEAVE FOR WORK AND THE CAR SHOWED A WARNING "CHECK HYBRID SYSTEM" AND THE CORRESPONDING WARNING LIGHT CAME ON. THE GASOLINE ENGINE ALSO STARTED RIGHT AWAY AND STAYED ON, EVEN THOUGH THE EV BATTERY WAS FULL. THE ENGINE REMAINED ON THROUGHOUT MY COMMUTE TO WORK AND BACK TO HOME IN THE EVENING. I PLUGGED THE CAR IN MY GARAGE FOR CHARGING OVERNIGHT WITH THE TIMER SET TO START THE CHARGING AT 10PM. AROUND 10:45PM, MY WIFE AND I OPENED THE INTERNAL GARAGE DOOR FROM INSIDE THE HOUSE AND IMMEDIATELY SMELLED EXHAUST FUMES AND HEARD THE ENGINE RUNNING. I OPENED THE GARAGE OVERHEAD DOOR RIGHT AWAY AND UNPLUGGED THE CHARGING CABLE WHICH TURNED THE ENGINE OFF. JUST TO BE SURE, I PLUGGED THE CABLE IN AGAIN AND TURNED OFF THE TIMER TO RESTART THE CHARGING IMMEDIATELY. AS SOON AS THE CHARGING STARTED, THE ENGINE CAME ON AND AFTER A FEW SECONDS STARTED REVVING UP ALSO. I IMMEDIATELY UNPLUGGED THE CHARGING CABLE AND ENGINE STOPPED. I TOOK THE CAR TO THE DEALER TODAY AND AM WAITING TO HEAR BACK FROM THE DEALER. I THINK THIS IS A POTENTIALLY SERIOUS SAFETY ISSUE AND HENCE I AM REPORTING IT.

FIRST EXTENDED DRIVE OF NEW CAR, CHECK ENGINE LIGHT CAME ON. TOOK IT TO DEALER FOR SERVICE, WAS TOLD I HAD "BAD FUEL" THAT THEY TESTED A SAMPLE AND FOUND E85 (ETHANOL) IN IT, WHICH IS NOT COVERED BY HYUNDAI NEW CAR WARRANTY FOR PLUG-IN HYBRID ELECTRIC VEHICLES. I PAID $828 TO HAVE FUEL DRAINED AND REPLACED, FUEL INJECTION CLEANING, AND DECARBONIZING AND THROTTLE BODY CLEANING. CHECK ENGINE LIGHT WENT AWAY, BUT TURNED BACK ON A FEW DAYS LATER. AGAIN TOOK IT TO DEALER BUT THEY WERE UNABLE TO GET IT TO TURN ON AFTER I LEFT IT, SO RETURNED THE CAR TO ME, NO CHARGE. I HAD ONLY ADDED 87 OCTANE GASOLINE (PER OWNER'S MANUAL RECOMMENDATION) TO MY CAR 3 TIMES PRIOR TO THE FIRST CHECK ENGINE LIGHT EPISODE, AT STATIONS THAT DID NOT SELL E85. DURING SUBSEQUENT CONVERSATION WITH HYUNDAI REP, WAS TOLD MAYBE WATER WAS IN GAS. BUT ENGINE RAN FINE AND I DROVE 100 MILES AFTER LAST GAS FILLUP SO I SUSPECT THERE MAY BE A PROBLEM WITH THE EMISSIONS SENSOR THAT MANIFESTS AS CHECK ENGINE LIGHT WITH RANDOM (INACCURATE) DIAGNOSTIC CODE. I GOT THIS CAR IN CHICAGO, BUT ILLINOIS IS NOT A LOW EMISSIONS VEHICLE STATE, SO THE PLUG-IN HYBRID IS NOT ALLOCATED TO HYUNDAI DEALERS IN ILLINOIS. THE SONATA HYBRID, HOWEVER, IS SOLD HERE BUT I DON'T KNOW IF IT SHARES THE SAME ENGINE/EMISSIONS SENSING SYSTEM AS MY PLUG-IN HYBRID ELECTRIC. DEALER SERVICE DID CHECK FOR OBVIOUS THINGS: GAS CAP, RESETTING THE ENGINE DIAGNOSTIC CHIP. I UNDERSTAND THE 2016 MODEL PHEV IS SUBSTANTIALLY THE SAME AS MY 2017 MODEL, IN CASE SIMILAR CHECK ENGINE LIGHT ISSUE HAPPENED WITH 2016 CARS.