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Alright, after waiting, and getting a mirror for myself, I visually could not se mine activated. I got a second opinion at another (more reputable shop) and it failed the inspection. Currently under the knife. Glad to hear I'm the only one however, quite impressed it lasted 11K miles.

On another note, I got to drive an Audi R8 for 2 days and WOW!
 

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Alright, after waiting, and getting a mirror for myself, I visually could not se mine activated. I got a second opinion at another (more reputable shop) and it failed the inspection. Currently under the knife. Glad to hear I'm the only one however, quite impressed it lasted 11K miles.

On another note, I got to drive an Audi R8 for 2 days and WOW!
Glad you're getting it fixed. I'm also amazed that it went so long without an issue, but I'll admit my mechanical incompetency... I don't exactly know what it does, besides the obvious tension, maybe only comes into play when the car is pushed really hard?
 

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Glad you're getting it fixed. I'm also amazed that it went so long without an issue, but I'll admit my mechanical incompetency... I don't exactly know what it does, besides the obvious tension, maybe only comes into play when the car is pushed really hard?
I’m actually very surprised also. The failures I’ve seen so far have all been on cars with very few miles.
 

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Glad you're getting it fixed. I'm also amazed that it went so long without an issue, but I'll admit my mechanical incompetency... I don't exactly know what it does, besides the obvious tension, maybe only comes into play when the car is pushed really hard?
Could be it, I daily drive it mostly highway easy driving as much as possible unless something comes about.
 

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Alright, after waiting, and getting a mirror for myself, I visually could not se mine activated. I got a second opinion at another (more reputable shop) and it failed the inspection. Currently under the knife. Glad to hear I'm the only one however, quite impressed it lasted 11K miles.

On another note, I got to drive an Audi R8 for 2 days and WOW!
Yours is the first one that I’ve seen fail the check. Glad you caught it before anything bad happened.
 
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Could you point me in the direction of someone whos gone through it? If theres a link.
Sorry, my post might have been a bit speculative. There were a couple of reported catastrophic valvetrain failures that were assumed to have been due to skipped timing. Your car is actually the first one I’ve seen that failed the TSB inspection.There was a car that was initially thought to have the issue but it ended up being a dealer not doing the check correctly.
 

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The tensioners have an internal spring, but primarily relies on oil pressure to keep the chain under tension. My understanding is the tensioner locks in place until it is activated, so it's not fighting against the engine builder when instaling the chain drives. If it's not activated, it's going to stay locked. Without any tension against the chains, they are loose and there's too much slack that can promote bad things happening. The harder you push it, the more likely that is to occur. If the sprocket can skip a tooth or two, you could have a valve kiss a piston, which is never a good outcome.

This is a secondary chain set up on an earlier DOHC engine. These are a lot harder to see with the VCT mechanism. The piece in the middle is the tensioner. The chains ride on plastic guides that are exerting pressure against the chain to keep the assembly under tension.

219103


If you didn't jump a tooth, and everything stayed in time, you probably don't have any engine damage.
 

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Alright, after waiting, and getting a mirror for myself, I visually could not se mine activated. I got a second opinion at another (more reputable shop) and it failed the inspection. Currently under the knife. Glad to hear I'm the only one however, quite impressed it lasted 11K miles.

On another note, I got to drive an Audi R8 for 2 days and WOW!
Hello
I have the 5th CFTP OFF THE LINE AT Flatrock Assembly plant.I do not think mine would have an issue.1700 miles not going to bother checking.
 

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Hello
I have the 5th CFTP OFF THE LINE AT Flatrock Assembly plant.I do not think mine would have an issue.1700 miles not going to bother checking.
If your car falls within the specified date range, I recommend either checking yourself or taking it to the dealer to have them check.
 

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The tensioners have an internal spring, but primarily relies on oil pressure to keep the chain under tension. My understanding is the tensioner locks in place until it is activated, so it's not fighting against the engine builder when instaling the chain drives. If it's not activated, it's going to stay locked. Without any tension against the chains, they are loose and there's too much slack that can promote bad things happening. The harder you push it, the more likely that is to occur. If the sprocket can skip a tooth or two, you could have a valve kiss a piston, which is never a good outcome.

This is a secondary chain set up on an earlier DOHC engine. These are a lot harder to see with the VCT mechanism. The piece in the middle is the tensioner. The chains ride on plastic guides that are exerting pressure against the chain to keep the assembly under tension.

View attachment 219103

If you didn't jump a tooth, and everything stayed in time, you probably don't have any engine damage.
Great Info! Thank you!!
 

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Hello
I have the 5th CFTP OFF THE LINE AT Flatrock Assembly plant.I do not think mine would have an issue.1700 miles not going to bother checking.
I would check it! Its very easy to see yourself. Unless you're in my boat where its still down. Otherwise it takes 2 minutes, for peace of mind.
 

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I would check it! Its very easy to see yourself. Unless you're in my boat where its still down. Otherwise it takes 2 minutes, for peace of mind.
Please click your upper right avatar/account settings/vehicle details and enter your car year. It then shows under your screen name, which helps in conversations here. We cover multiple years of the GT500 on this forum.

Also, we encourage everyone to put their first name in their signature to make this place more friendly.
 

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The tensioners have an internal spring, but primarily relies on oil pressure to keep the chain under tension. My understanding is the tensioner locks in place until it is activated, so it's not fighting against the engine builder when instaling the chain drives. If it's not activated, it's going to stay locked. Without any tension against the chains, they are loose and there's too much slack that can promote bad things happening. The harder you push it, the more likely that is to occur. If the sprocket can skip a tooth or two, you could have a valve kiss a piston, which is never a good outcome.

This is a secondary chain set up on an earlier DOHC engine. These are a lot harder to see with the VCT mechanism. The piece in the middle is the tensioner. The chains ride on plastic guides that are exerting pressure against the chain to keep the assembly under tension.

View attachment 219103

If you didn't jump a tooth, and everything stayed in time, you probably don't have any engine damage.
Thanks! --- I figured it was something like this - but wasn't sure. I only vaguely remember helping my dad fix my car after what I thought was a timing belt ('79 Mustang).
 

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Even chains will stretch and develop slack over time and use, when there was none to begin with. With brand new chains on the secondary system (cams) on the 5.4/5.8, they're really tight. I presume the Coyote system is the same. How much VCT changes those dynamics, I don't know. As they loosen up, they can cause cam timing errors, without a tensioner. It gets worse the longer the chain, such as those on the primary system. A gear drive system would be better, but it would be noisy.

I can see getting away with an unemployed tensioner with a new engine for a while, but at some point the chains will develop enough slack that a failure is inevitable. With 760 hp, it can happen sooner than later if you call on it more frequently. Hopefully this problem doesn't surface with the 2021s. I feel like I should check mine, just because.
 

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Even chains will stretch and develop slack over time and use, when there was none to begin with. With brand new chains on the secondary system (cams) on the 5.4/5.8, they're really tight. I presume the Coyote system is the same. How much VCT changes those dynamics, I don't know. As they loosen up, they can cause cam timing errors, without a tensioner. It gets worse the longer the chain, such as those on the primary system. A gear drive system would be better, but it would be noisy.

I can see getting away with an unemployed tensioner with a new engine for a while, but at some point the chains will develop enough slack that a failure is inevitable. With 760 hp, it can happen sooner than later if you call on it more frequently. Hopefully this problem doesn't surface with the 2021s. I feel like I should check mine, just because.
It is an easy check for peace of mind (assuming you have an appropriate mirror or decent bore-scope)
 
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