NHTSA owner reports · September 18, 2026 snapshot.
Engine complaints
25 reportsClear category filter70,500 miles · May 12, 2016
Electrical SystemEngineExterior Lighting
RECENTLY MY LOW BEAM HEADLIGHTS WOULD RANDOMLY STOP WORKING. AT FIRST THEY WOULD GO OFF AND COME BACK ON AFTER A COUPLE MINUTES BUT NOW I'L BE LUCKY IF THEY TURN ON AT ALL. THE PROBLEM COMES FROM THE FUSE BOX LOCATED UNDER THE HOOD. IN THE BEGINNING I WOULD GET OUT OF MY CAR AND PLAY AROUND WITH THE LOW BEAM RELAY UNTIL THE LIG…
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RECENTLY MY LOW BEAM HEADLIGHTS WOULD RANDOMLY STOP WORKING. AT FIRST THEY WOULD GO OFF AND COME BACK ON AFTER A COUPLE MINUTES BUT NOW I'L BE LUCKY IF THEY TURN ON AT ALL. THE PROBLEM COMES FROM THE FUSE BOX LOCATED UNDER THE HOOD. IN THE BEGINNING I WOULD GET OUT OF MY CAR AND PLAY AROUND WITH THE LOW BEAM RELAY UNTIL THE LIGHTS CAME ON AND STAYED ON BUT NOW THAT DOES NOT EVEN HELP. ITS OBVIOUSLY A PROBLEM DUE TO THE FUSE BOX. I KNOW THERE ARE MANY OTHER CORVETTE OWNERS WHO HAVE THE SAME ISSUE. I HOPE GM WILL FIX THIS PROBLEM.
NHTSA ODI #10864505
17,200 miles · Mar 13, 2016
Engine
ENGINE VALVES NOISY AND SHOWED EXCESSIVE WEAR AT 17,000 MILES. CONCERNS THAT THE ENGINE COULD FAIL WHILE THE VEHICLE IS IN MOTION, RENDERING POWER STEERING AND POWER BRAKES INOPERABLE, RISKING A CRASH. HAD CYLINDER HEADS REPLACED AS A PRECAUTION TO PREVENT A POTENTIAL DROPPED VALVE.
NHTSA ODI #10846353
13,500 miles · Feb 23, 2016
Engine
HAD TO HAVE THE HEADS REWORKED BECAUSE OF BAD GUIDES AT 13,500 MILES. CAR OUT OF WARRANTY GM DOES NOTHING AND CLAIMS THERE ISN'T A PROBLEM. STOCK 2008 Z06 WITH 13,500 MILES ALL (8) EXHAUST OUT OF SPEC, (3) INTAKE OUT OF SPEC (5) INTAKE ONLY IN SPEC BY .0001-.0004 MEASUREMENT DONE BY KATECH/WCCH CAN PROVIDE DATA IF NEED…
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HAD TO HAVE THE HEADS REWORKED BECAUSE OF BAD GUIDES AT 13,500 MILES. CAR OUT OF WARRANTY GM DOES NOTHING AND CLAIMS THERE ISN'T A PROBLEM. STOCK 2008 Z06 WITH 13,500 MILES ALL (8) EXHAUST OUT OF SPEC, (3) INTAKE OUT OF SPEC (5) INTAKE ONLY IN SPEC BY .0001-.0004 MEASUREMENT DONE BY KATECH/WCCH CAN PROVIDE DATA IF NEEDED
NHTSA ODI #10837653
47,000 miles · Jan 17, 2016
Engine
VALVE GUIDES ON HEADS WERE OUT OF SEPCIFICATION AND WIGGLED VISIBLY WITH SLIGHT SIDE PRESSURE, EVEN WHEN LOADED. HEADS R&R'D AT A COST OF $2500
NHTSA ODI #10820719
24,000 miles · Jan 5, 2016
Engine
ENGINE DROPPED EXHAUST VALVE WHILE THE ENGINE WAS TURNING 6800 RPM IN THIRD GEAR AT 118 MPH. THE ENGINE STOPPED RIGHT AT THE TIME I WENT TO SHIFT TO 4TH GEAR AND THE TACH DROPPED TO ZERO. I PULLED THE CAR INTO A RUN OFF AREA AND GOT OUT OF THE CAR BECAUSE I THOUGHT IT MIGHT BE ON FIRE DUE TO ALL OF THE SMOKE.
NHTSA ODI #10818171
18,200 miles · Aug 12, 2015
Engine
I HAD TO REPLACE THE EXHAUST VALVES IN MY 2008 Z06 IN ORDER TO PREVENT CATASTROPHIC FAILURE. REPLACED 2-PIECE SODA FILLED VALVES WITH 1 PIECE STAINLESS STEEL VALVES. UPON INSPECTION VALVE GUIDES ON #3 HAD EXCESS SLOP. SENT HEADS OUT FOR MACHINING AND NEW GUIDES. STOCK ENGINE HAD LESS THAN 20K MILES. MANUFACTURER OF ENGINE…
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I HAD TO REPLACE THE EXHAUST VALVES IN MY 2008 Z06 IN ORDER TO PREVENT CATASTROPHIC FAILURE. REPLACED 2-PIECE SODA FILLED VALVES WITH 1 PIECE STAINLESS STEEL VALVES. UPON INSPECTION VALVE GUIDES ON #3 HAD EXCESS SLOP. SENT HEADS OUT FOR MACHINING AND NEW GUIDES. STOCK ENGINE HAD LESS THAN 20K MILES. MANUFACTURER OF ENGINE HAS ISSUED SERVICE BULLETINS ACKNOWLEDGING THESE ERRORS EXIST.
NHTSA ODI #10748155
14,923 miles · Aug 7, 2015
Engine
THE LS7 ENGINE HAS A DEFECT THAT CAUSES ACCELERATED VALVE GUIDE WEAR. CONTINUING TO DRIVE THE CAR WILL EVENTUALLY LEAD TO A VALVE DROPPING AND CAUSING CATASTROPHIC ENGINE FAILURE. ONCE THIS OCCURS THERE WILL BE A LOSS OF POWER STEERING, POWER BRAKES, AND WATER/OIL COULD GET ON THE TIRES LEADING TO A LOSS OF CONTROL OF THE CAR. I…
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THE LS7 ENGINE HAS A DEFECT THAT CAUSES ACCELERATED VALVE GUIDE WEAR. CONTINUING TO DRIVE THE CAR WILL EVENTUALLY LEAD TO A VALVE DROPPING AND CAUSING CATASTROPHIC ENGINE FAILURE. ONCE THIS OCCURS THERE WILL BE A LOSS OF POWER STEERING, POWER BRAKES, AND WATER/OIL COULD GET ON THE TIRES LEADING TO A LOSS OF CONTROL OF THE CAR. IN A FEW CASES FIRE HAS ERUPTED. HERE ARE TWO VIDEOS OF THE ISSUE HAPPENING: HTTPS://WWW.YOUTUBE.COM/WATCH?V=TM4MDCIX-KI HTTPS://WWW.YOUTUBE.COM/WATCH?V=ZLT7DJNKVNY LUCKILY I FOUND THE EXCESSIVE VALVE GUIDE WEAR BEFORE THE ENGINE FAILED, BUT IT COST ME $3000 TO HAVE THE HEADS REBUILT. UPDATED 09/15/15*LJ *CN
NHTSA ODI #10747110
40,000 miles · Feb 27, 2015
Engine
I WAS CONCERNED ABOUT EXCESSIVE VALVE TRAIN NOISE AND AFTER READING SEVERAL CORVETTE FORUM THREADS ABOUT IMPROPERLY MACHINED HEADS BY GM'S SUPPLIER LINAMAR, AND THAT NUMEROUS VEHICLES HAVE HAD VALVES DROP AND RUIN THE ENGINES, I TOOK MY CAR WITH 40000 MILES ON IT TO A CHEVROLET DEALER TO HAVE MY VALVE GUIDE CLEARANCE TESTED. I H…
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I WAS CONCERNED ABOUT EXCESSIVE VALVE TRAIN NOISE AND AFTER READING SEVERAL CORVETTE FORUM THREADS ABOUT IMPROPERLY MACHINED HEADS BY GM'S SUPPLIER LINAMAR, AND THAT NUMEROUS VEHICLES HAVE HAD VALVES DROP AND RUIN THE ENGINES, I TOOK MY CAR WITH 40000 MILES ON IT TO A CHEVROLET DEALER TO HAVE MY VALVE GUIDE CLEARANCE TESTED. I HAD INTAKE VALVE GUIDES OUTSIDE OF SERVICE SPECIFICATIONS, EXHAUST VALVE GUIDES OUTSIDE OF SERVICE SPECIFICATIONS, AND A COMBINATION OF OTHER INTAKE AND EXHAUST VALVE GUIDES AT OR NEAR THE MAXIMUM OUTSIDE OF SERVICE SPECIFICATIONS. THE CAR IS BEING REPAIRED WITH NEW HEADS AND GUIDES. GM NEEDS TO ISSUE A RECALL ON THIS ISSUE, THERE HAVE BEEN NUMEROUS ENGINE FAILURES AS A RESULT OF A DROPPED VALVE INTO A CYLINDER WHICH CAN CAUSE ACCIDENTS AND FIRES. GM IS VERY AWARE OF THIS ISSUE, BUT REFUSES TO DO ANYTHING ABOUT THIS HUGE SAFETY RISK TO DRIVERS, PASSENGERS, AND NEARBY VEHICLES IF THE ENGINE FAILS GOING DOWN THE ROAD. *TR
NHTSA ODI #10691188
28,000 miles · Feb 7, 2015
Engine
DURING MODERATE ACCELERATION AND MID RANGE RPMS, THE ENGINE CATASTROPHICALLY FAILED ON THE HIGHWAY. A HOLE WAS BLOWN IN THE ENGINE BLOCK AND THE CAR SPEWED SMOKE, OIL AND CHUNKS OF METAL FROM THE ENGINE ALL OVER THE ROAD AS I VEERED OFF ONTO THE SHOULDER. THE SUSPECTED ISSUE WAS FAULTY HEADS AND IMPROPERLY MACHINED VALUE GUIDES.…
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DURING MODERATE ACCELERATION AND MID RANGE RPMS, THE ENGINE CATASTROPHICALLY FAILED ON THE HIGHWAY. A HOLE WAS BLOWN IN THE ENGINE BLOCK AND THE CAR SPEWED SMOKE, OIL AND CHUNKS OF METAL FROM THE ENGINE ALL OVER THE ROAD AS I VEERED OFF ONTO THE SHOULDER. THE SUSPECTED ISSUE WAS FAULTY HEADS AND IMPROPERLY MACHINED VALUE GUIDES. THIS ENGINE WAS REPLACED UNDER WARRANTY. THE SECOND ENGINE HAD AN ISSUE WITH THE CLEARANCE BETWEEN THE CRANKSHAFT AND THE PISTON ARM. AFTER APPROXIMATELY 4500 MILES ON THE SECOND ENGINE, THE CAR LOCKED UP AND DIED IN THE MIDDLE OF TRAFFIC CAUSING A MASSIVE TRAFFIC JAM FOR ABOUT HALF AN HOUR. I HAD TO PUSH THE CAR BY HAND IN TRAFFIC TO THE FARTHEST EDGE OF THE RIGHT HAND LANE SINCE THERE WAS NO SHOULDER. AFTER THE CAR COOLED DOWN FOR HALF AN HOUR I WAS ABLE START THE VEHICLE AND MAKE IT TO A DEALER. THIS ENGINE WAS ALSO REPLACED UNDER WARRANTY. *JS
NHTSA ODI #10681927
42,000 miles · Jan 28, 2015
Engine
CHECKED ENGINE HEADS AND VALVES DUE TO THE ONGOING ENGINE FAILURES OF THE LS7 ENGINE. NUMBER 7 INLET VALVE WAS FOUND TO BE STRESSED TO THE POINT OF IMMINENT FAILURE DUE TO THE FACTORY MACHINING BEING OUT OF ALIGNMENT WITH THE VALVE STEM AND THE VALVE SEAT. 2 OTHER INLET VALVES WERE FOUND NOT CONCENTRIC AND WERE REPLACED ALSO. …
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CHECKED ENGINE HEADS AND VALVES DUE TO THE ONGOING ENGINE FAILURES OF THE LS7 ENGINE. NUMBER 7 INLET VALVE WAS FOUND TO BE STRESSED TO THE POINT OF IMMINENT FAILURE DUE TO THE FACTORY MACHINING BEING OUT OF ALIGNMENT WITH THE VALVE STEM AND THE VALVE SEAT. 2 OTHER INLET VALVES WERE FOUND NOT CONCENTRIC AND WERE REPLACED ALSO. THE EXHAUST VALVES WERE FOUND TO BE OUT OF FACTORY SPECIFICATIONS WITH THE VALVE GUIDES SO ALL 16 VALVE GUIDES AND 8 EXHAUST VALVES WERE REPLACED ALSO AND THE HEADS MACHINED TO FACTORY SPECIFICATIONS. WHEN THESE ENGINES FAIL, THE ENGINE STOPS AND YOU HAVE NO POWER STEERING OR VACUUM POWER TO THE BRAKES SO YOU STRUGGLE TO STOP THE CAR AND STEER IT TO A SAFE PLACE. THE ENGINE BLOCK, BEING ALUMINUM, NORMALLY VENTILATES WITH A CONROD OUT THE SIDE AND OIL AND COOLANT IS DEPOSITED ON THE ROAD SURFACE. NOT A GOOD SITUATION IN MY OPINION AS WE DRIVE OUR CAR ON MAJOR HIGHWAYS FAIRLY REGULARLY. GENERAL MOTORS IS AWARE OF THE SITUATION AND SO FAR HAS DONE NOTHING TO SHOW ANY CONCERN FOR THE MOTORIST WHO OWNS THE CAR OR THE INNOCENT MOTORIST MINDING HIS/HER OWN BUSINESS ON THE HIGHWAY. *TR
NHTSA ODI #10679435