my worst fear, might've finally happened...

IMO, if there was a broken valve floating around inside the motor there'd be all kind of ruckus and something imploding or exploding before you drove any 80 miles. I'm trying to imagine that valve head bouncing around in the cylinder and just letting you keep driving along with nothing but a flashing light on the dash...........seems extremely farfetched. If any valvetrain item breaks the car isn't going anywhere except to the side of the road pretty much instantly.......................discuss

If anything there will be a slight tick on that valve, they seldom close all the way if there is a seat issue, that creates excess clearance and noise.

The one time I've seen a broken valve in person, there was just a piece missing, like in the video below.

https://www.youtube.com/watch?v=xyY5xt4LmPw&t=341s

You are right though, there would be a misfire all the time, this isn't a "once in a blue moon" issue.
 
Well, if a tiny screw off a butterfly valve from VICS makes the amount of noise and damage it does, I can't imagine the crazy that would happen if the end of the valve was bouncing around in there or even a piece off it. That s*** would break plug end and would not get past rings. Drop the exhaust manifold and see what's there. It would have to go somewhere and the car would not run anything near normal enough to drive 80 miles....not that I could imagine in any way.
 
The screws on the butterfly valves are on the intake and would get drawn into the combustion chamber.

A little piece of exhaust valve would most likely be blown out of the cylinder before it had a chance to fall in.

However, I still don't think the cel would only flash after driving a while with no compression on cylinder #2. (and it may be on at first because of his other codes)
And his car would run like crap,.. Not just in limp mode.

I still think he just needs coils, plugs and wires especially if his compression is good.
 
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Yeah I feel you but they said they tested all 4 and nothing. I'll try to do this tomorrow

When you say "nothing", do you mean they found nothing wrong with the cylinder or that there was no compression ??

If they found nothing wrong with the cylinder, and you have full compression, then there is something else wrong with that cylinder.

If you had been misfiring for a while before the test you could have completely fouled the cylinder and a new coil, plug and wire may not be able to fire in it.

(carbon buildup reduces the volume of the combustion chamber and increases pressure).

Everything still boils down to a compression test.
 
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You could rub your codes (or disconnect your battery for ten minutes) then drive it and see if the cel comes on right away and if it's flashing and see how long it takes.

Both codes P0138 and P0140 need two drive cycles to turn on the cel.
 
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The screws on the butterfly valves are on the intake and would get drawn into the combustion chamber.

A little piece of exhaust valve would most likely be blown out of the cylinder before it had a chance to fall in.

However, I still don't think the cel would only flash after driving a while with no compression on cylinder #2. (and it may be on at first because of his other codes)
And his car would run like crap,.. Not just in limp mode.

I still think he just needs coils, plugs and wires especially if his compression is good.

Actually these screws and flaps dont necessarily get drawn in but its possible. A while back I found this issue for Dubs car. Valve screw fell out and kept smacking the spark plug wire shut- this will Immediately cause a flashing cell
 
I took it into the shop and they deducted that apiece of a valve is broken off. They said for the work to be done and thats not including misc part or other things they might find wrong along the way to an amount of $2k so at this point i think I might be looking at a new engine

According to the shop, they used diff coils and plugs to test the other cylinders and it was just the #2 that kept giving an error.

Yeah I feel you but they said they tested all 4 and nothing. I'll try to do this tomorrow

Never go to that shop again.

It's elementary mechanics that a broken valve is properly diagnosed with compression test and boroscope, not by switching coils and plugs around hoping to cure a misfire. This shop is plainly trying to bend you over.

Subscribed for compression test results.
 
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