Fuel pump / Fuel tank Cracks due to bad plastic use by

- Georgetown, TX, USA

I had a valve drop and threw a rod thru my engine traveling at highway speeds on a busy highway. I lost engine power, power steering, and spilled oil and other chemicals onto the roadway. A thick cloud of smoke billowed from underneath and out the back of the car making it unsafe for cars traveling behind me. The dealer who has since inspected my car has stated it is a known issue that the "lifters are weak". after quite a bit of reading, it appears many other owners of the same car have experienced a multitude of issues with valves, lifters, heads, etc. GM is aware of faulty parts but I cannot find any notice of recalls. Make/model: 2009 Corvette Z06; engine: LS7.

- Edmond, OK, USA

Valves were out of spec it came from the factory this way

- Crowley, TX, USA

Valve guide measurements were out of specifications at 5K miles

- Peotone, IL, USA

My engine experienced valve guide failure while driving which resulted in a complete loss of power and spilled oil all over the road. The entire engine was destroyed. If I had not been able to pull over safely it could have been very dangerous.

- Oakland, CA, USA

I experienced an engine failure. This resulted in a sudden and complete loss of power at an unexpected time. This occurred during a high performance driver education event at auto club speedway in fontana, ca. There was no warning before the moment the engine failed. The cause of the failure was the head of one of the exhaust valves separated from the valve stem and fell into the cylinder, destroying the cylinder head, piston and cylinder wall. The engine model in my 2009 Corvette is the LS7. A google search on 'LS7 dropped valves' will fill many pages.

- San Diego, CA, USA

Valve guides worn - all- out of specification at 30K miles, heads removed and valve guides and exhaust valves replaced.

- Dripping Springs, TX, USA

Fuel leak

- Wellington, FL, USA

Had to have cylinder heads rebuilt because manufacturing issue with valve guids wearing quickly out of spec and if not corrected destroying the entire motor. I got a check engine light with misfire which was caused by worn guides. Sent heads into be rebuilt and found out that they were way out of spec. Some at.030 and spec cut off at.006

- West Jordan, UT, USA

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 27000 miles on it to a Corvette specialty shop to have my valve guide clearance tested. I had (2) intake valve guides outside of service specifications, (4) exhaust valve guides outside of service specifications, and a combination of (10) other intake and exhaust valve guides at or near the maximum outside of service specifications. The car is being repaired with proper re-machining of the heads to make the valve guides concentric, new intake and exhaust valve guides installed, as well as new seals, valves, springs, etc. 88% of the Corvette forum members who have had their cylinder heads tested for excessive valve guide wear, were out of service specifications. Source: Https://www.corvetteforum.com/forums...-registry.html 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.

- Alexandria, PA, USA

Regarding the cylinder heads, I am one of hundreds that experienced intake and exhaust valves that were out of specification due to inadequate cylinder head design and valve guides. As a result, I needed to have my heads replaced with rebuilt heads and new valve guides. The uploaded document highlights the measurements on the valves as being out of specification after they were tested upon removal from my vehicle. On an engine with only 11,000 miles at the time, this is alarming. Hundreds others have experienced the same defect. This is a safety issue as when a valve drops, it falls into the engine having the effect of potentially immediately seizing it up which would then cause the car to lock the rear wheels and lose control

- Zionsville, IN, USA

Although my car is a 2009 it only has 300 miles on it. The ZO6 model which has the "LS7 engine has a known valve issue with both intake and exhaust being out of spec and wearing rapidly. I had a "wiggle test" done on all my valves. More than half of the 16 valves were out of spec. If the issue is not correct a valve will drop and a new engine will be required.

- Long Beach, CA, USA

Engine valve train subject to complete failure due to improper manufacture causing a total engine failure an possible loss of control at speed.

- Colorado Springs, CO, USA

I was concerned about excessive valve train noise and after reading several Corvette forum threads and speaking to numerous Chevrolet mechanics about improperly machined heads by GM's supplier linamar, and that numerous vehicles have had valves drop and ruin the engines. This has happened on completely stock vehicles. People with less than 20000 miles have lost motors. 88% of the Corvette forum members who have had their cylinder heads tested for excessive valve guide wear, were out of service specifications. Source: www.corvetteforum.com/forums/...-registry.html 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. If the engine fails due to dropping a valve, the engine will immediately shut off, which cuts off power steering and power braking. This is a very huge safety concern.

- Taylorsville, NC, USA

Valve guide issue causing failure to brakes, and power steering, as well as engine blowing

- Spring, TX, USA

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 37,000 miles on it to courtesy Chevrolet / Cadillac to have my valve guide clearance tested. I had (3) intake valve guides outside of service specifications, (7) exhaust valve guides outside of service specifications, and a combination of (11) other intake and exhaust valve guides at or near the maximum outside of service specifications. The cost of proper re-machining of the heads to make the valve guides concentric, new intake and exhaust valve guides installed, as well as new seals, valves, springs, etc. Is something I simply cannot afford at the moment with the downturn of the oilfield industry. Please bear in mind, my car had a replacement LS7 engine from a dropped exhaust valve before I owned it, so this has already happened to my car once. It occurred at 22xxx miles, and can have the GM dealer print a copy of the ro line to prove it. This is occurring at an alarming rate, but after our warranty period, we the consumer are left out to dry. 88% of the Corvette forum members who have had their cylinder heads tested for excessive valve guide wear, were out of service specifications. Source: www.corvetteforum.com/forums/...-registry.html 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. Please assist us in having GM make this right.

- Youngsville, LA, USA

GM denies any sort of wide spread issue with respect to the manufacturing/assembly of the cylinder heads for the LS7 engine. There have been numerous catastrophic engine failures as a result of a broken valve head dropping into the cylinder and subsequently blowing a hole through the motor, causing fluids to leak all over the road, and complete loss of control of the vehicle. The symptoms are premature valve guide wear, which eventually become so worn that the valve closes on the wrong angle to the seat, and off breaks the valve head. The issue appears to be poor valve guide to valve seat concentricity, which leads to premature valve guide wear. My 2009 Z06 Corvette at only 15,000 street driven miles was inspected by a reputable third party repair facility, and discovered that 14/16 valve guides were beyond GM's service limit, and the remaining 2/16 were right at the limit. This is something that shouldn't occur until 150,000 miles at least...not 15,000. There needs to be an investigation before more catastrophic failures occur. There are hundreds if not thousands of documented occurrences.

- Honolulu, HI, USA

The LS7 engine is known to have bad 2 piece exhaust valves that come apart and fall into the cylinder resulting in a catastrophic engine failure that requires an entire new engine. This happened to me this past March 2015. 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.

- Schiller Park, IL, USA

There was a manufacturing error made during engine build with the valve guides. They are making a noise currently. This can cause the engine to fail abruptly and consequently one could lose power (engine) and thus loose braking assist & power steering assist and can cause a crash & could be fatal.

- Rockwall, TX, USA

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 7800 miles on it to a Corvette specialty shop ( katech) to have my valve guide clearance tested. I had (5) intake valve guides outside of service specifications, (4) exhaust valve guides outside of service specifications, and a combination of (3) other intake and exhaust valve guides at or near the maximum outside of service specifications. The car is being repaired with proper re-machining of the heads to make the valve guides concentric, new intake and exhaust valve guides installed, as well as new seals, valves, springs, etc. 88% of the Corvette forum members who have had their cylinder heads tested for excessive valve guide wear, were out of service specifications. Source: www.corvetteforum.com/forums/...-registry.html 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. Here is a link with the guide measurements in it. www.corvetteforum.com/forums/C6-Z06-discussion/3608443-katech-stage-2-Z06-sn-74-a.html.

- Peotone, IL, USA