Chevrolet Corvette knocking problems

Filed Jun 26, 2025 · Engine · LA

Engine needed to be replaced and it was but new engine misfiring and throwing knock codes and misfire codes. Contacted General Motors only to be told they can’t do anything about it and that’s unacceptable. Case number [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Apr 15, 2019 · Engine · 20,000 miles · CA

Ls7 engine makes loud "ticking" sound at idle to ~ 2,000 RPM caused by defective cylinder heads which were improperly machined by gm's subcontractor. Local chevrolet dealers said the noise is "normal"... But when heads opened and valve and valve guides measured, excessive valve and valve guide wear documented. Local gm dealer & $4,350 gm protection plan (extended warranty that I had to buy to cover this $5,000 repair) refused to repair so I had to drive it 5 hours to another gm dealer to get it repaired under my gmpp extended warranty. Many other 2006 to 2015 corvette owners have experienced this same excessive valve wear including some owners valves breaking and destroying their $16,000 ls7 motors while spewing oil and metal everywhere. This also resulted in a fear of driving this car, a significant "diminishment of value" of this vehicle, and complicated its resale (buyers had heard about these catastrophic ls7 motor failures.

Filed Aug 31, 2016 · Fuel system · 22,625 miles · CA

This car has 23,000 miles on it and I am the original owner. It has developed some sort of fuel leak one of the two fuel tanks or the connecting tube while sitting parked the garage. Gm has know about this issue for years. They did not warn owners of these cars of this problem. Now that I have this issue I have discovered the gm would fix this if you discovered this problem in ten years or 100,000 miles. This is a major safety issue, the car could explode if a person walks by it in a parking lot, in an accident or parked in a parking structure. This car is now a ticking bomb due to the failure of gm to notify owners or this potential problem. All corvettes are not daily drivers that is why the mileage is low. There are many cars out there with this problem. It is important that gm should have to notify all owners of this vintage of car of this issue and fix them before people get hurt or killed. Not only the owners of these vehicles are at risk, so is the general public.

Filed Feb 1, 2016 · Engine · 54,000 miles · AR

Excessive valve train noise, engine noise, knocking.

Filed Oct 22, 2015 · Engine · 7,794 miles · CA

Engine knock on 6.2 liter engine. When the vehicle sits a knocking occurs in the engine upon startup. It is not a lifter knock, but a knock deeper in the engine gm has noted the problem and made multiple repairs (6+) cam shaft changed but no lifters. Thought this was odd as the wearing surfaces are now dissimilar .gm said this is all they authorized. Knock still present gm then removed upper end of engine. Noted extreme carbon build up on multiple pistons. One piston had so much building apparently close to valves hitting. Gm tech advised engine replacement, gm authorized cleaning of pistons: guess what, knock still present the knocking is a piston or lower end knock. Similar to wrist pins or rod bearing caps or bearings. When knocking occurs engine is rough and pulsates. Time ranges from 30 seconds to couple of minutes after multiple gm repairs knock is still present, noticed engine performance is not the same and with lack of stability fuel economy has dropped

Filed Oct 9, 2014 · Engine · 3,645 miles · TN

I saved for 3 years to purchase a new 2014 corvette. It was broken in properly and was well maintained. It was 3 months old and had 3,645 miles when on the way to work it threw a rod bearing and the engine died.the car lost all power. Luckily, I was able to coast my car to the side of the road but it was very dangerous during 7:30 am rush hour traffic with no power on in the vehicle. It has taken gm over a month to fix the car, which ended up in a full engine replacement. My brand new top of the line chevy product had the whole front end disassemble at the dealer and re-installed. I told gm I was not confident about this work but they insisted everything would be like new. I had the car for 3 days when smoke started to come from under the hood. I took the car back to correct this issue, a quality issue with paint, rear trunk seal, and to clean up cosmetic damage (replacing more parts) from the installation of the new engine. I know this is not your organization purpose to monitor quality but all of this lead to the fact that gm has issues with this car. I asked the dealer if the car was being analyzed by technicians and they stated they would just get the parts back and work the problem. I do know that gm has 3 tsb related to engine replacements or what to do after an engine is replaced on a car that is less than a year old. Car and driver reported engine damage and there are at least two other members of the corvette forum that had severe engine damage. This problem is a safety issue. If I could not have made it to the side of the road, I could have been hit from the rear or struck by traffic walking across major freeway. It has been in the shop now for more than 30 days of my 120 days of ownership. It is back again for another 7 to 10 days. I asked gm to help me replace it but they have refused saying they will keep repairing it.

Filed May 9, 2013 · Electrical, Engine · 8,000 miles · CA

I've had repeated failures that have required multiple repairs 1. Engine knocking- repeated repairs, upper end replaced knocking and engine roughness still there 2. Transmission- failure of clutch plates, replaced problem not resolved, transmission slipping is increasing 3. Electrical system failure: the electrical system completely shuts down, nothing operates even the hazard warning lights- this has occurred a minimum of 8 times. Relays, switches wiring battery get extremely hot until battery bleeds down. High potential for electrical fires and car cessation of operations have left us in perilous conditions on multiple occasions.

Filed Oct 5, 2012 · Body · 50,000 miles · TX

Roof laminate was replaced as part of a manufacturer recall a few years ago. But cracking noise continued until today after a loud knock, the driver side of the roof started leaking air badly. Pulled over and noticed the roof body and not just the laminate had separated from its frame. Opened roof latches and while removing the detachable roof, both rear metal pins that mechanically hold the roof to the frame fell to the ground. Threaded section of both pins had sheared off and roof was only held in place by the rear center hook. Apparently material and pin design is not appropriate for the torque that the roof goes through against the frame during normal driving resulting in complete separation of the roof.

Filed Aug 16, 2012 · Engine, Transmission · 28,000 miles · GA

Squeaking noise from engine accessory drive belts, clunking/ knocking noise at lower front of engine. The crank shift blancer split apart moving back to the engine. Damage to the timing chain cover and oil pan causing oil to leak.

Filed Feb 13, 2010 · Engine · 45,224 miles · CA

2005 corvette, 45,224 miles. Squeaking noise from engine accessory drive belts, clunking/ knocking noise at lower front of engine. Found crankshaft balancer retaining bolt backed out, crankshaft balancer moving forward. Had this bolt come out further, it would have damaged the steering rack, accessory belts coming off, loss of power steering, electrical, braking. This issue is known by gm/chevrolet, tsb 05-06-01-001d. Vehicle was flat bed towed to dealer, they denied that there was a problem with the bolt, it just needed new belts. After threatening the dealer & gm with a lawsuit if the pulley came off and resulted in property damage or bodily injury, they would replace the pulley with the upgraded one & a new bolt per the tsb, but at customer expense. Repairs completed 2/10/2010. This vehicle was within the VIN number range for the tsb, but the dealer was more concerned where the paper copy of gm tsb 05-06-01-001d came from- this is public information. Please- make this issue a formal recall before someone gets hurt. The federal safety agency database shows at least 6 similar incidents, many others have not been reported to the federal safety agency.