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The engine light is on for a cylinder 1 misfire and the engine light flashes
Fix this NOW. MAYBE you can still save the catalyst. Maybe. (Probably not, given the amount of time the misfire has been going on. Might as well budget for catalyst replacement, and then hope for the best.)

I also had it checked over and there is spark and fuel to that cylinder but little to no compression.
That sounds expensive.

Next step is to do a cylinder leakdown test. Find out where the compression is going. If you hear air escaping out the throttle body, the intake valve doesn't seal. If you hear air escaping out the tailpipe, the exhaust valve isn't sealing. Either way, you're likely pulling the cylinder heads for a "valve job".

If you see air bubbles in the coolant, you've got a cracked casting, or perhaps a failed head gasket. Again, the head(s) are coming off.

You're going to hear air escaping at the oil fill (remove the cap), the question is "how much", which is why you need the leakdown tester--so you can use the pressure gauge(s) to determine acceptable leakage from excessive leakage.

When it was my money, I bought a leakdown tester intended for Continental/Teledyne aircraft-engine use. The important parts are the orifice size (.040, for engines with a bore size of 5" or less, tapered inlet) and the Master Orifice which allows you to "test the tester". Without the Master Orifice, you need to use the tester on several "Known-Good" cylinders having the same bore size as the engine you're trying to diagnose. At minimum, you'd need to test the other seven cylinders that aren't giving you trouble, and compare the results to the reading from the Problem Child.

 
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Guys he said little to no compression. Is it possible that the exhaust valve is stuck open?
Sure. How much damage did it do when the piston hit it? Valve seized in the guide? Bent valve?

Any way you look at it, that head is coming off for repairs if there's no compression.
 

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I think it's really "swept volume" of the cylinders that are the testing criteria, since one engine with a 5" bore and a 3/4" stroke is gonna be miles different from an engine with a 5" bore and a 10" stroke.
Nope.

The leakage is past the rings. Bore diameter has a major impact on ring circumference, and ring end-gap, both of which have an effect on leakage. Big bore = tendency towards more leakage. Smaller bore = tendency for less leakage.

The cylinder length/stroke length is of no importance for leakdown testing, since the piston is held at TDC or very close. Which works out well, as "most" cylinders have the most wear at the top, so not only are you testing ring leakage, but you're testing it in the part of the bore that's most-likely to be worn, and within a few crankshaft degrees of maximum cylinder pressure when the engine runs. Some folks do the leakdown testing at about 7--10 degrees past TDC, but I don't bother.

So--for engines with a bore diameter of less than 5", a .040 orifice in the leakdown tester is correct.
 

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In a cylinder already known to have "no" compression, a static test is a wonderful way to verify intake vs. exhaust valve seal, and (low-pressure) leaks into the cooling system. Used with care, it's good for spotting leakage into the crankcase via worn/broken rings or holes in the piston. I've been doing "1960-ish" low pressure leakdown testing since the late 1980s; I've found it to be extremely useful.

A dynamic test like you describe can plot cylinder pressure vs. degrees of crank rotation; but doesn't tell you where the compression is going. The transducer in the plug hole isn't measuring leakage past rings, past either valve, or into the coolant. Right? And you'd never hear the leakage at the throttle body or tailpipe with the crank turning.

PS: What equipment are you using from Snap-On that does this--Modis/Vantage + pressure transducer?
 

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However there is an easier way to fix it.
I did this and it worked perfect.
I tried watching the video, and it won't play properly for me. I get about ten seconds of audio, with a still picture. Then it buffers for thirty seconds, giving me another ten seconds of audio with a different still picture.

Short story: What the hell is he doing? Freeing up the lifter plunger with a needle scaler? Or is the lifter body stuck in the lifter bore? And when he finishes, it's still knocking like mad until he finishes the test-drive.

Why not replace the defective lifter(s)? This doesn't seem to me to be a long-term fix.
 

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He is using the rod to mechanically release the lifter. During operation Oil pressure collapses the lifters used for the DOD and are different than normal hydraulic lifters as they mechanically slide together to deactivate the valve. Over time, and in some cases abuse from infrequent oil changes they wear from the collapsing of them and they get stuck. You take the rod and it pushes on the lifter to separate the two pieces. It is a genius solution.

If you do this I would recommend changing the oil shortly thereafter as you will leave some shavings from the process...

Here is some information on DoD works Document ID# 1417658 2005 Ponti
1. Except for using oil pressure to release the lock-pins, these appear to be solid lifters, not hydraulic. There's no mechanism for hydraulic pressure to take up clearance from wear. At least, that's how your link describes them.

2. Either he'd beating on the lifter body, which doesn't bode well for the lifter roller, roller axle, or cam lobe; or he's beating on the lifter plunger which doesn't make sense since it's already in the collapsed position--and which doesn't bode well for the roller, roller axle, or cam lobe. Genius solution? Seems barbaric to me.

3. If the lifters get "stuck" from "wear", I'd think that the real solution is to replace them with lifters that aren't worn.

Is there something I don't understand?
 
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The diagram in your link shows no mechanism for hydraulic lash adjustment. It shows a plunger that's either locked in place with pins, or collapsed to the bottom of the lifter body.

Apparently, the diagram has been "simplified" for "clarity".

Beating on the lifter is still a very bad idea. At least take the poor thing out of the engine before whacking on it, so no impact is transferred through the roller, roller pin, or onto the cam lobe.
 
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