Huge Coolant Leak

Yes.
You could have a leaking head gasket or a crack in the cylinder head.
After driving the car for a few days the spark plug should show signs of coolant on the tip.
You may want to do a compression test to see if that cylinder is low on compression too.

You might want to look for a vacuum leak on the intake manifold. You also might need to hook up a scope and measure injector duty cycle and compare it with a good cylinder. Also check wiring for chaffing going to the injectors and coil pack. I can provide you with pin out on ECM if you need.

I would start with the inlet manifold gasket, these are know to break down causing vacuum leaks which can cause this issue, also check around engine for other vacuum leaks

If you run the OBD II codes,it'll give you an idea. I would suspect the usual offenders......old spark plugs,wiring,or coil pack problem.
An EGR can cause jerking and dying, but so can a vacuum leak,usually accompanied by rough idle before the engine dies.
I just did my sister-in-law's plugs,wiring, and coil pack in THAT order,because the code only showed `MISFIRE,cyl. #2.'
Even though the plugs and wiring were pretty worn,it turned out the coil pack had gone bad.
Also,how long since you replaced your fuel filter? don-ohio (:^)

Problems could include but are not limited to a bad spark plug, wire, coil pack, fuel injector, ECM, vacumn leak, poor compression and/or coolant in the cylinder.

YOU HAVE INTAKE MANIFOLD LEAK ALSO COULD HAVE BAD OR STICKING INTAKE VALVES. CODE PO 226 IDM SIGNAL NOT RECEIVED AND CODE PO 542 FUEL PUMP SECONDARY CIRCUIT.

I'm wondering if you could have a burnt exhaust valve cause by the exhaust leak in the cylinder where the exhaust leak was.

It can be a bad spark plug, plug wire, burnt valve, blown head gasket, or worn piston rings. Replace the spark plugs and plug wires and see if the miss goes away. If it does not then have a compression test run on the engine. In addition if you are loosing coolant with no apparent leak, and you see white smoke coming from the exhaust you may have a blown head gasket which will cause a miss.

could be a fuel problem or a fuel injector. these engines are also bad to leak water at the intake manifold gaskets, if coolant leaks internally it would kill the spark and cause a misfire. if its not low on coolant though i'd keep checking fuel and fire

did the car over heat for long?
there could possibly be damage to your head like warping due to overheating and blowing a head gasket or something along those lines .
first check the oil dipstick is it milky?
then check the coolant is it oily?
and when it is running is it blowing any white smoke?
if you replaced the plugs and it is misfiring did you plug the wire all the way back on the plugs if not then the problem is a plug wire being loose and loosing connection with the plug.
sounds like a simple fix if you don't have water in your oil or white smoke coming out the exhaust.
troubleshooting it can be a bigger job but if you nail the right symptoms down you can corner the problem.
like if it is a coil pack or bad wire switch them with another one and see if the problem follows the wire or coil pack.for instance take the number one plug wire off and the number two wire off and put the number one wire on number two and see if the number one misfires. if so then the wire is the problem if not then try numbers three and four until you find out which cylinder is the culprit.
good luck and happy hunting.