imaginager

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My motor also has a 21175 build date. I took mine in for a vicious rattle on start-up one month ago. The dealer has diagnosed an issue with the cam phasers that they're waiting on parts to fix. In the meantime the dealer gave me a loaner F150 that I'd rather drive when it's cold and rainy anyway, but if I'm prolonging the wait on my engine blowing up I'd rather get it over with all at once.
How many miles do you have on it, if you don't mind saying?
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JollyFolly

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So…roughly 4500 miles in, I think my engine has blown. Car lost power to the engine as I was driving, alert flashed on the dash to put car in park and restart engine. As I drifted to get out of the traffic to the side of the road, car became engulfed in smoke from the tailpipe with a sort of burnt smell to it.
June 8th engine build. 21159.
So update for yah, blown engine. Cylinder #5. I am not a big car guy, so not sure what that means. They said internal failure. They are still diagnosing and will have a more formal update for me tomorrow.
For all the car guys on here, what else would need to be replaced? How bad is this?
For everyone else, what would you do in my situation? Take a replaced motor? Ask for a buyback and look for something new/different? Ask for an extended/extended warranty?
Also does anyone have a good # for Ford HQ customer service? I want to call them.
 

SPITmadFIRE

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I have a Bronco, that means that I have 2 doors. ;)

IMG-49de4644f9249eb941727b4851a2fb4e-V.jpg


Ya, it's a pig normally because I have a heavy foot.

My highway average is about 17 mpg though.
Saved plenty of weight by going 2dr instead of 4dr -- enough to tow a brand new 2.7L crate motor with you wherever you go 🥲

All jokes aside, love the look of your 2dr. The wheel and low-profile winch combo are great.
 

SPITmadFIRE

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So update for yah, blown engine. Cylinder #5. I am not a big car guy, so not sure what that means. They said internal failure. They are still diagnosing and will have a more formal update for me tomorrow.
For all the car guys on here, what else would need to be replaced? How bad is this?
For everyone else, what would you do in my situation? Take a replaced motor? Ask for a buyback and look for something new/different? Ask for an extended/extended warranty?
Also does anyone have a good # for Ford HQ customer service? I want to call them.
"Blown engine" doesn't give us much to go off of, unfortunately -- I would ask your service advisor for as much information on the failure as possible. If they're saying "blown engine" one can only assume there's enough damage to the piston, cylinder wall, head, etc. to warrant a full engine replacement.

ELI 16: engine "timing" refers to everything that has to do with keeping the various engine functions in sync with one another -- when the piston starts to move down to intake air, the intake valve needs to be open and gas needs to be injected; when the piston comes back up to compress that air and gas, the valves need to be closed; when the piston reaches the top of that compression stroke, the spark plug needs to fire; and so on. If these things get out of sync, bad things occur. Air/gas mixture can explode before the piston is in the right position, causing the engine to work against literal explosions in the cylinder (explosions are usually the winner in the long run). Valves can open at the wrong time, causing the piston to slam into the valves and destroy one another. If your engine failure is like the others noted here, it's likely that a valve in cylinder #5 inside your engine somehow got out of timing, or got disconnected entirely and "dropped" into the cylinder. This causes metal to crash into metal over and over again, instantly destroying your engine from the inside out. There's not much you could've done to avoid that.

ELI 5: imagine your pistons are big, sharp, metal industrial fans -- your fingers are the valves. You have superhuman speed, and while the fans are spinning you can put your fingers in between the blades and remove them before they get chopped off. Somehow, your whole arm got in between the fan blades and got stuck in that position. You can visualize what happened next as the fan and your arm introduce themselves to one another.
 
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SPITmadFIRE

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The highest mileage reported so far with a dropped a valve was 4500.

So in my head I have 5k as the magic number for basically all the gremlins. After checking all the known issues (like loose plugs, nuts, and wires, things rubbing on drive lines, etc), I think if I can make it to 5k, I'll be in the clear.
The highest mileage failure reported was 4,500mi, but it was reported only two days ago. There's no way you could extrapolate from 22 incidents listed here, the most recent of which being the highest mileage, that we have any idea if any mileage ceiling exists on these failures. Even worse, there hasn't been any conclusive evidence presented that shows the engines Ford is currently putting into vehicles in production aren't affected.

The vast majority of Broncos on the road are well under the 5,000 mile range I would imagine, given we're only just now hitting peak production. I would expect to see some 5,000-10,000mi failures in the coming weeks.
 
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Carbon Bronco

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So update for yah, blown engine. Cylinder #5. I am not a big car guy, so not sure what that means. They said internal failure. They are still diagnosing and will have a more formal update for me tomorrow.
For all the car guys on here, what else would need to be replaced? How bad is this?
For everyone else, what would you do in my situation? Take a replaced motor? Ask for a buyback and look for something new/different? Ask for an extended/extended warranty?
Also does anyone have a good # for Ford HQ customer service? I want to call them.
See if they can tell you if it was an intake or exhaust valve.
 

JollyFolly

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"Blown engine" doesn't give us much to go off of, unfortunately -- I would ask your service advisor for as much information on the failure as possible. If they're saying "blown engine" one can only assume there's enough damage to the piston, cylinder wall, head, etc. to warrant a full engine replacement.

ELI 16: engine "timing" refers to everything that has to do with keeping the various engine functions in sync with one another -- when the piston starts to move down to intake air, the intake valve needs to be open and gas needs to be injected; when the piston comes back up to compress that air and gas, the valves need to be closed; when the piston reaches the top of that compression stroke, the spark plug needs to fire; and so on. If these things get out of sync, bad things occur. Air/gas mixture can explode before the piston is in the right position, causing the engine to work against literal explosions in the cylinder (explosions are usually the winner in the long run). Valves can open at the wrong time, causing the piston to slam into the valves and destroy one another. If your engine failure is like the others noted here, it's likely that a valve in cylinder #5 inside your engine somehow got out of timing, or got disconnected entirely and "dropped" into the cylinder. This causes metal to crash into metal over and over again, instantly destroying your engine from the inside out. There's not much you could've done to avoid that.

ELI 5: imagine your pistons are big, sharp, metal industrial fans -- your fingers are the valves. You have superhuman speed, and while the fans are spinning you can put your fingers in between the blades and remove them before they get chopped off. Somehow, your whole arm got in between the fan blades and got stuck in that position. You can visualize what happened next as the fan and your arm introduce themselves to one another.
They will be giving me a more in depth analysis tomorrow. I’ll update once I have it.
 

SPITmadFIRE

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They will be giving me a more in depth analysis tomorrow. I’ll update once I have it.
Thanks for keeping us up to date! I can only imagine how much of a bummer it is to have a new car literally blow up like that, so thanks for being a team player and giving us all the info you can get. Fingers crossed you get a fresh, unaffected engine soon!
 

Razorbak86

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So update for yah, blown engine. Cylinder #5. I am not a big car guy, so not sure what that means. They said internal failure. They are still diagnosing and will have a more formal update for me tomorrow.
For all the car guys on here, what else would need to be replaced? How bad is this?
Here are a few links that will help explain how the engine works and what kind of damage valve failures can cause.

If you spend a few minutes on these links, you will be better prepared to talk to your dealer and hopefully discuss more specifics with the service technician who examines the engine and prepares the write-up...

1) How a Car Engine Works

This is a detailed 3D animation of the internal components of a modern engine. It explains the combustion process and identifies a lot of the parts that will likely show up on the repair write-up.

2) What a Dropped Valve Does to an Engine

This is a short YouTube video of a Caterpillar C15 engine (similar to a car engine) that shows what the inside of the engine looks like when a valve drops into the combustion chamber.

3) Valve Failures Explained

This is a more detailed discussion, from an engine builder's perspective, explaining the different types of valve failures and how to diagnose them. (The failure descriptions here are relevant, but the repair discussions are not, because your engine will likely be replaced with a complete, new engine.)

Hope this helps.
 

Boxer4

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SPITmadFIRE

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New design Bronco 2.7 oil pan- requiring 7 quarts ?
Are oil starved cam phasers possible ?
This would be the clusterfuck of all clusterfucks if the wrong dipstick is causing engine failures... isn't 7qts the correct fill, confirmed by the engineers? But the dipstick is a 6qt dipstick?
 
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