2007 Hyundai Sonata engine problems

ENGINE

I have a 2007 Hyundai Sonata SE v6 3.3L and on January 9th, 2026 I had an incident where on the road my charging system light on signifying alternator failure. I made it home, but the battery was dead which was recently purchased. After recharging the battery I conducted tests with a multimeter and have determined the alternator has failed. The alternator has accrued a coating of oil overtime that was unknown until my research into the matter of root cause. Hyundai manufactures a V6 engine family called Lamba in which a version called Lambda MPi G6DB was introduced in 2007–2009 Hyundai Santa Fe (CM) and 2005–2009 Hyundai Sonata (NF) models. In 2023 Hyundai issued a recall for the 2007-2009 Santa Fe for a Cylinder Head Cover Oil Leak Repair where oil drips from the valve cover directly onto the alternator causing it to fail. I have a 2007 Hyundai Sonata 3.3L V6 engine where the very same issue has occurred with photo evidence that has caused my alternator to fail and have tested the issue. This vehicle model was not included in the recall despite the engine being exactly the same as the recalled model, the year being the exact same as the Santa Fe, and the alternator in the exact placement where the oil drips into the alternator causing failure just like the Santa Fe recall. The Santa Fe recall with the same issue is documented with National Highway Traffic Safety Administration below: [XXX] Hyundai has yet to issue the same recall for the Hyundai Sonata brand of vehicles, despite the same issue occurring and a known issue with the Lambda MPi G6DB engine design effecting multiple models in the same way documented across multiple owners of these vehicles with various fixes suggested on Youtube, Reddit, and enthusiast forums for this engineering failure that causes considerable risk if the alternator fails in operation on roadways. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA complaint #11717330 — an unverified report by a vehicle owner.

ENGINE

2007 Hyundai Sonata- Consumers son is emailing on behalf of his elderly mother. He is requesting any kind of help in reference to a catastrophic engine failure. Complaint has been filed with the MA Attorney Generals Office and the email mentions a current NHTSA investigation into the 2007 Sonata.

NHTSA complaint #11522891 — an unverified report by a vehicle owner.

ENGINE

The contact owns a 2007 Hyundai Sonata. The contact stated while performing a daily check on the vehicle, the contact became aware that oil was leaking onto the alternator. The vehicle was taken to an independent mechanic and the mechanic replaced the driver’s side valve cover gasket. The dealer was contacted, and the dealer stated that the vehicle was not under recall and referred the contact to the manufacturer for assistance. The manufacturer was contacted, and the manufacturer stated that the vehicle was not under recall. The failure mileage was 114,000.

NHTSA complaint #11515544 — an unverified report by a vehicle owner.

ENGINE

The contact owns a 2007 Hyundai Sonata. The contact stated that while driving at various speeds the vehicle drove sluggish and unresponsive and would not properly accelerate. Upon inspection it was discovered that engine oil from the valve cover gasket had leaked onto the alternator. The vehicle was taken to the local mechanic who diagnosed that the alternator was damaged due to the presence of oil inside and needed to be replaced. The vehicle was not yet repaired. The contact indicated that the vehicle was previously serviced by the manufacturer to prevent the failure from occurring but the failure had occurred on two separate occasions. No further information was available. The manufacturer and local dealer were not notified of the failure. The failure mileage was 151,000.

NHTSA complaint #11463447 — an unverified report by a vehicle owner.

ENGINE

VALVE COVER LEAKS ONTO ALTERNATOR, CAN CAUSE SUDDEN POWER LOSS AND PREMATURE ALTERNATOR FAILURE. I'VE BEEN RESEARCHING THIS ISSUE AND OTHER PEOPLE HAVE HAD THIS EXACT THING HAPPEN. APPARENTLY ONCE YOU GET THE VALVE COVER GASKET FIXED, IT WILL FAIL AGAIN IN ANOTHER YEAR OR SO. THERE IS A DEFECT EITHER IN THE GASKET OR THE VALVE COVER MATING SURFACE. CURRENTLY MY CAR IS ONLY AT THE STAGE OF OIL LEAKING FROM COVER GASKET AND GETTING ONTO THE ALTERNATOR. NO FURTHER FAILURE HAS HAPPENED YET. MY CAR HAS 67,000 MILES.

NHTSA complaint #11412960 — an unverified report by a vehicle owner.

ENGINE

TL* THE CONTACT OWNS A 2007 HYUNDAI SONATA. THE CONTACT STATED THAT WHILE DRIVING AT VARIOUS SPEEDS, SHE HEARD RATTLING AND TAPPING SOUNDS. THE VEHICLE LOSS MOTIVE POWER WHILE ACCELERATING. THE VEHICLE WAS TAKEN TO AN INDEPENDENT MECHANIC AND INFORMED THAT THERE WAS A ROD KNOCK AND VALVE TAP PRESENT AND THAT THE ENGINE NEEDED TO BE REPLACED. KEARNY MESA HYUNDAI (4797 CONVOY ST, SAN DIEGO, CA 92111) WAS CONTACTED AND INFORMED THAT THE VEHICLE HAD TO BE REPAIRED OUT OF POCKET. THE VEHICLE WAS NOT REPAIRED. THE MANUFACTURER WAS NOT NOTIFIED OF THE FAILURE. THE FAILURE MILEAGE WAS 99,800.

NHTSA complaint #11406415 — an unverified report by a vehicle owner.

ENGINE

ON OCTOBER 18, 2019 MY FUEL PUMP BROKE IT HAPPENED AT A PLAZA PARKED AND THEN ON FEBRUARY 10, 2019 WAS INVOLVED IN A CAR CRASH DUE TO A BALL JOINT FROM THE FRONT END PASSENGER SIDE. MY BALL JOINT BROKE AND EVERYTHING ELSE DETACHED IT HAPPENED ON THE HIGHWAY I WAS WITH MY KIDS AND THANK GOD I DIDN'T CRASH INTO A CAR BUT IT WAS A VERY SCARY TRAUMATIC MOMENT FOR ALL OF US. I KEEP REPLACING THE INNER AND OUTER TIE ROD, ALSO THE BALL JOINT AND NOW IT MAKES SENSE WHY, IT HAS TO DO WITH THE CONTROL ARM. I'M REPORTING THIS NOW BECAUSE I LOOKED INTO THE SAFETY RECALLS TODAY AND FOUND SO MANY MY VEHICLE FALLS UNDER THESE LISTINGS AND I NEVER RECEIVED A LETTER STATING THE SAFETY RECALLS TO BRING MY CAR TO THE DEALERSHIP. I HAVE PICTURES TAKEN WHEN MY CAR BROKE DOWN, BUT DON'T HAVE IT AVAILABLE RIGHT NOW I CAN PROVIDE IT AFTERWARDS AND I HAD MY CAR TOWED.

NHTSA complaint #11350165 — an unverified report by a vehicle owner.

ENGINE

I FIRST NOTICED THE VALVE COVER GASKET LEAKING ONTO THE ALTERNATOR AT ABOUT 121,000 MILES AND AT 140.000 MILES I HAD THE VALVE COVER GASKET REPLACED, THERMOSTAT, INTAKE PLENNOM GASKET ALSO. AND HAD THE ALTERNATOR REPLACED AFTER IT FAILED BECAUSE OF THE OIL LEAKING ONTO IT AT 156,092. LUCKILY I JUST DROVE BY MY MECHANICS GARAGE AT ABOUT 50 MPH AND ABOUT A MILE PASSED HIS GARAGE THE CAR STARTED TO BUCK AND STALL AND ALL THE DASH BOARD LIGHTS WERE FLASHING ALONG WITH THE CD TURNING ON AND OFF ALONG WITH THE SEAT BELT LIGHT WHICH WAS FLASHING ON AND OFF WHEN IT WAS BUCKLED FOR ABOUT 1 MONTH PRIOR TO THIS FAILURE. I ACTUALLY MADE IT TO HIS GARAGE BEFORE IT SHUT DOWN IN HIS PARKING LOT.

NHTSA complaint #11280223 — an unverified report by a vehicle owner.

ENGINE

MY TRANSMISSION WENT

NHTSA complaint #11234385 — an unverified report by a vehicle owner.

ENGINE

I HAD BEEN DRIVING ON THE TURNPIKE FOR ALMOST AN HOUR WHEN I STARTED TO HEAR A CLICKING NOISE. I WAS DRIVING ABOUT 70 MPH AND PRESSED DOWN ON THE ACCELERATOR. WHEN I DID SO, THERE WAS A LOUD BANG AND SUDDENLY, SMOKE FILLED UNDER THE HOOD AND ALSO CAME OUT THE EXHAUST PIPE. I ALSO SAW DEBRIS FLEW OUT FROM UNDER THE CAR, LOOKING LIKE IT WAS COMING FROM THE TAIL PIPE. I PULLED OVER AND OPENED THE HOOD TO FIND OIL EVERYWHERE, MORE SMOKE FLOODING OUT OF THE HOOD AND BITS OF METAL DEBRIS ALL OVER. OIL WAS LEAKING ALL OVER THE SIDE OF THE ROAD. THE MECHANIC HAS JUDGED THAT THE ENGINE BURST WHILE I WAS DRIVING IT.

NHTSA complaint #11209947 — an unverified report by a vehicle owner.

ENGINE

1. THE CHECK ENGINE LIGHTS CONTINUALLY GOES ON AND STAYS ON

NHTSA complaint #11207214 — an unverified report by a vehicle owner.

ENGINE

OIL LEAK FROM VALVE COVER GASKET DROPPED ON ALTERNATOR. DAMAGE TO ALTERNATOR CAUSED VEHICLE TO SHUT OFF WHILE GOING 60MPH ON AN INTERSTATE. MULTIPLE LIGHTS ON THE DASH ILLUMINATED (INCLUDING THE ENGINE AND BATTERY LIGHTS, THE SEAT BELT LIGHT STARTED FLASHING), I LOST POWER TO THE RADIO AND THE LIGHTS INSIDE THE CAR STOPPED WORKING, QUICKLY AFTER THESE TWO ISSUES STARTED I LOST THE ABILITY TO ACCELERATE (AGAIN, WHILE GOING 60MPH ON AN INTERSTATE). VERBATIM TEXT FROM COMPLAINT 14V415000 FOR THE HYUNDAI VERACRUZ (INCLUDING THE MODEL YEAR 2007)- "AN UNEXPECTED FAILURE OF MOTIVE POWER WHILE DRIVING INCREASES THE RISK OF A CRASH." I BELIEVE THAT THIS RECALL SHOULD BE EXPANDED TO OTHER HYUNDAI VEHICLES AS THERE ARE A NUMBER OF OTHER COMPLAINTS ONLINE FOR SONATAS FOR MULTIPLE YEARS, INCLUDING 2007. MY LOCAL DEALERSHIP QUOTED ME $1372.43 TO REPLACE THE ALTERNATOR, VALVE COVER GASKET, AND BATTERY (ATTACHED).

NHTSA complaint #11184175 — an unverified report by a vehicle owner.

ENGINE

TIMING CHAIN TENSIONER WANT IT REPLACED

NHTSA complaint #11149554 — an unverified report by a vehicle owner.

ENGINE

REAR CROSS MEMBER , NOT GOOD , TRANSMISSION , AND ENGINE OIL PAN PODRIDO , AIR CONDITIONER NOT TO GOOD , DOOR HANDLER PROBLEM ,,, ETC

NHTSA complaint #11118532 — an unverified report by a vehicle owner.

ENGINE

HYUNDAI REPLACED ORIGINAL ENGINE THAT EXPLODED WITH A REBUILT ENGINE THAT SUFFERED SAME FATE WHILE DAUGHTER WAS EVACUATING FROM HURRICANE IRMA ON INTERSTATE 95

NHTSA complaint #11098266 — an unverified report by a vehicle owner.

ENGINE

2007 HYUNDAI SONATA. CONSUMER WRITES IN REGARDS TO ENGINE FAILURE. *LD

NHTSA complaint #11093110 — an unverified report by a vehicle owner.

ENGINE

VEHICLE IN MOTION ON FREEWAY IN RUSH HOUR TRAFFIC, SPEED VARYING FROM 0-30 MPH. ENGINE SPONTANEOUSLY BEGAN MAKING LOUD METALLIC KNOCKING NOISE WHEN ACCELERATOR WAS PRESSED. NO ENGINE WARNING LIGHT ACTIVATED. MECHANIC FOUND NO LOSS OF OIL PRESSURE. FRONT END DISASSEMBLY SHOWED METAL BITS IN THE OIL PAN. ENGINE CONSIDERED TO BE UNSAFE TO DRIVE DUE TO THREAT OF FIRE. CAUSE BELIEVED TO BE CRANKSHAFT BEARINGS.

NHTSA complaint #11065682 — an unverified report by a vehicle owner.

ENGINE

VEHICLE WAS IN MOTION AND ENGINE BEGAN KNOCKING. STOPPED DRIVING IT. REMOVAL OF ENGINE HAS SHOWN THAT IT HAS THROWN A ROD AND SPUN THE INSERT OUT OF IT. THIS HAS HAPPENED ON OTHER HYUNDAI VEHICLES BUT THE RECALL ISN'T GOING BACK FAR ENOUGH.

NHTSA complaint #11052075 — an unverified report by a vehicle owner.

ENGINE

FOR THE SECOND TIME, I HAVE HAD OIL LEAKING OUT OF THE VALVE COVER OR TIMING BELT COVER ONTO THE ALTERNATOR. SO MUCH SO, THAT THE ALTERNATOR BECOMES SOAKED AND "SHORTS OUT" ACCORDING TO A HYUNDAI DEALER. MECHANICS WHO HAVE REPAIRED THIS ALL AGREE THAT THIS IS A HAZARD AND PUBLIC SAFETY ISSUE. "FIRE RISK" AND "SUDDEN COMPLETE LOSS OF CONTROL AT HIGHWAY SPEEDS" WERE BOTH MENTIONED. HYUNDAI STATES THAT MY VEHICLE IS OUT OF WARRANTY DUE TO MILEAGE AND SAYS THAT THERE IS NO RECALL FOR THIS PROBLEM DESPITE THE OBVIOUS RISKS THAT THEIR MECHANICS AND OTHER MECHANICS MENTION. AFTER VERY LITTLE EFFORT IN RESEARCHING THIS PROBLEM ON THE INTERNET, IT IMMEDIATELY BECAME OBVIOUS THAT THIS IS A COMMON RECALL FOR HYUNDAI CONCERNING THIS ENGINE(3.3L V6). THE RECALLS NAME OTHER HYUNDAI PRODUCTS BUT FOR SOME REASON SKIP MY VEHICLE EVEN THOUGH TWO REPS AT HYUNDAI CUSTOMER SERVICE STATE THAT "YOU ARE DESCRIBING THE EXACT SAME PROBLEM". WE HAVE SPENT CLOSE TO $1000 ON THIS ONE ISSUE IN THE LAST YEAR. IT NEARLY CAUSED MY WIFE TO BE STRANDED ON THE INTERSTATE 10HRS FROM HOME. AND HYUNDAI ADMITS THAT IT IS AN ISSUE BUT BECAUSE MY VIN IS NOT LISTED, THEY REFUSE TO HELP FIX OR REFUND ANY THING THAT HAS ALREADY BEEN SPENT ON THIS MANUFACTURE DEFECT. AGAIN, I EMPHASIZE THAT THIS IS A PUBLIC SAFETY HAZARD THAT NEEDS TO BE ADDRESSED. DESPITE RECENT REPAIR, THIS PROBLEM STILL CONTINUES. THE VEHICLE WAS TRAVELING AT 70MPH EACH TIME THIS ISSUE OCCURRED. I HAVE RECORDS OF REPAIR FROM INDEPENDENT MECHANICS AND STATEMENT FROM HYUNDAI STATING THIS PROBLEM. THIS OCCURRED AT 118,000 AND 132,000 MILES. IT SEEMS LIKE IT OCCURRED PRIOR TO THIS AS WELL(LOOKING FOR RECORDS).

NHTSA complaint #11004350 — an unverified report by a vehicle owner.

ENGINE

2007 HYUNDAI SONATA. CONSUMER WRITES IN REGARDS TO ENGINE FAILURE. *LD THE CONSUMER STATED THAT THE ENGINE BLOCK HAD A CRACK IN IT. THE CONSUMER BELIEVED THAT THE FAILURE WAS PREMATURE. THE ENGINE WAS REPAIRED AND THE CONSUMER REQUESTED TO BE REIMBURSED. THE ENGINE WAS OUT OF WARRANTY

NHTSA complaint #10985330 — an unverified report by a vehicle owner.

ENGINE

TL* THE CONTACT OWNS A 2007 HYUNDAI SONATA. WHILE DRIVING 40 MPH, THE ENGINE SEIZED AND THE CHECK ENGINE AND OIL WARNING INDICATORS ILLUMINATED. THE VEHICLE WAS TOWED TO AN INDEPENDENT MECHANIC WHO DIAGNOSED THAT THE ENGINE NEEDED TO BE REPLACED. THE VEHICLE WAS REPAIRED, BUT THE FAILURE RECURRED. THE MANUFACTURER WAS NOT MADE AWARE OF THE FAILURE. THE FAILURE MILEAGE AND VIN WERE UNKNOWN.

NHTSA complaint #10995110 — an unverified report by a vehicle owner.

ENGINE

THE ISSUE IS THE TENSIONER FOR THE TIMING CHAIN. THE TENSIONER FAILED, CAUSING A VERY EXPENSIVE ENGINE REPAIR. THERE IS A RECALL ON THE 6 CYL TENSIONER, BUT NOT THE 4 CYL WHICH I HAVE. MY RESEARCH SAYS THE SAME TENSIONERS WERE USED FOR BOTH ENGINES. IT FAILED AT 169,000. IT WAS STATIONARY IN A PARKING LOT WHEN IT FAILED TO START. IT WOULD TURNOVER BUT WOULD NOT CATCH. I HAVE ALL THE DAMAGED PARTS SAVED BY THE MECHANIC. IF I WAS DRIVING WHEN IT FAILED, IT WOULD HAVE NOT ONLY BLOWN THE ENGINE BUT MOST LIKELY WOULD HAVE STOPPED MY CAR ON WHATEVER ROAD I WAS DRIVING ON, INCLUDING AN EXPRESSWAY.

NHTSA complaint #10953811 — an unverified report by a vehicle owner.

ENGINE

THIS CAR HAS THE FRONT VALVE COVER GASKET LEAK THAT OTHER HYUNDAI VEHICLES WITH THE V6 ENGINE. IT ONLY LEAKS RIGHT IN THE SAME CORNER AS ALL THE OTHERS AND IT LEAKS RIGHT ON TO THE ALTERNATOR. I AM ON MY SECOND MAYBE THIRD ALTERNATOR. I AHVE BEEN LUCKY ENOUGH TO HAVE IT NOT CAUSE ANY INJURY'S SO FAR.

NHTSA complaint #10903837 — an unverified report by a vehicle owner.

ENGINE

SAME PROBLEM AS DESCRIBED IN 14V415000 HYUNDAI VERACRUZ RECALL. WHILE DRIVING THE ESC WARNING LIGHT ON, THEN INTERMITTENT BATTERY + SEAT BELT INDICATING ALTERNATOR FAILURE, CAUSED BY LEAKING VALVE COVER. CAN CAUSE SUDDEN FAILURE. THIS DEFECT IS NOT ISOLATED TO THE VERACRUZ AND PERHAPS THE RECALL SHOULD BE BROADENED

NHTSA complaint #10876569 — an unverified report by a vehicle owner.

ENGINE

ENGINE MAKES A VERY LOUD NOISE AND CANNOT BE USED. THIS CAR WAS VERY WELL MAINTAINED AND JUST OUT OF WARRANTY. LOUD NOISE IN CYLINDER AND CRANK SHAFT. HYUNDAI SAYS ENGINE NEEDS TO BE REPLACED. THIS CAN HAPPEN TO ANYONE WHO WOULD BE LEFT STRANDED OR IN A BAD SITUATION. HYUNDAI DOES ACKNOWLEDGE A PROBLEM, BUT SO FAR NO RECALL.

NHTSA complaint #10876180 — an unverified report by a vehicle owner.

ENGINE

THE ENGINE STARTED MAKING METALLIC CLICKING AND KNOCKING NOISES ABOUT A WEEK AGO. I TOOK IT TO MY MECHANIC AND BY THEN IT STARTED SQUEAKING AND SQUEALING. HE SAID IT WAS CATASTROPHIC ENGINE FAILURE AND ASKED IF I HAD EVER LET IT RUN OUT OF OIL, WHICH I NEVER DID. WHEN DRIVING TO MY MECHANIC, LOST A LOT OF POWER ON AN ENTRANCE RAMP TO HIGHWAY AND ALMOST GOT IN AN ACCIDENT. MY MECHANIC NEVER SEEN IN AN ENGINE WITH < 200,000 MILES UNLESS AN OIL EVENT, SO HE BELIEVES THIS WAS DUE TO A MANUFACTURING DEFECT. IT IS INTERESTING THAT THE 2011 AND 2012 SONATA WAS RECALLED FOR EXACTLY THIS TYPE OF ISSUE AS WELL. I WONDER IF THE PROBLEMS WERE ALSO EXISTING ON PREVIOUS YEAR MODELS, SUCH AS THE 2007 MODEL.

NHTSA complaint #10860173 — an unverified report by a vehicle owner.

ENGINE

TRAVELING AT 50 MPH HIGHWAY OFF RAMP. A RATTLING IN THE ENGINE - BROKEN ROD - LOSS OF POWER AND NO ACCELERATION.

NHTSA complaint #10821215 — an unverified report by a vehicle owner.

ENGINE

NUMEROUS ISSUES FROM ALMOST DAY ONE WITH THIS CAR. 1) WITHIN LESS THAN A MONTH AFTER PURCHASE OF THIS VEHICLE, PASSENGER AIRBAG LIGHT WAS COMING ON EVEN WITH SOMEONE WEIGHING WELL OVER 100 LBS IN SEAT. DEALERSHIP BRUSHED IT OFF AS 'SOMEONE SITTING IN THE SEAT INCORRECTLY'. THE LIGHT STAYED ON FOR SO LONG, WITH THE DEALERSHIPS REFUSING TO DO ANYTHING, THAT WE FEEL IT EVENTUALLY BURNED OUT. 2) ENGINE LIGHT CAME ON VERY EARLY IN OWNERSHIP AS WELL AND DEALERSHIPS REFUSED TO RESOLVE. HAD TO HAVE FUEL SYSTEM REPLACED AT ONE POINT BECAUSE CAR COMPLETELY DIED WHILE DRIVING WITH PLENTY OF FUEL. 3) REPLACE HEADLAMPS, BRAKE LAMPS, AND TAG LAMPS ON A REGULAR BASIS. ON AT LEAST A MONTHLY BASIS WE ARE REPLACING 1 OR 2 LIGHTS. WE'VE BEEN PULLED OVER NUMEROUS TIMES BECAUSE A LIGHT HAS FAILED. 4) DRIVER DOOR AUTOMATIC LOCK NO LONGER WORKS. 5) AIRBAG LIGHT ON DRIVER SIDE CAME ON AROUND 2013 OR 2014 AND REMAINS ON. 6) PASSENGER SIDE VISOR DOESN'T STAY UP WHEN NOT IN USE. DRIVER SIDE VISOR IS STARTING TO DO THE SAME. 7) PASSENGER SEAT BELT LIGHT CONSTANTLY FLASHES EVEN WHEN SEAT IS EMPTY.

NHTSA complaint #10776565 — an unverified report by a vehicle owner.