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Could you describe the misfire, do you lose total power and engine stall or you just feel a temporary loss of power, i suggest doing as follow.

Put a good pair of gloves and shake the spark plugs wires bundle in a low light condition if you start seing spark going out of the wires then change wires
( dont be cheap ) change all of them

If no sparks can be seen then try to change your coil
it may be trying to say i am dying

Check both battery ( and connectors ) an alternator in some conditions you may have low voltage therefore the coil might not receive enough power

There is way more reasons for that misfire try the simple once first then go for the more complicated ones
 

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Discussion Starter · #4 ·
It only misfires when it's been warmed up and under load. I changed out the coil pack and plugs, got no response. Once I started tearing into it, I found 3 cracked injectors, and spots where you can see bleed through on the manifold gasket. I'm changing the oil pan due to damage from taking out an unruly O2 sensor.
I cleaned the intake manifold out, and scraped some massive carbon from the ports. I'll let you know how it turns out...
 

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Try the fuel regulator/ filter located in front of the tank.
 

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Discussion Starter · #6 ·
Putting it all back together tomorrow. Got a few vacuum leaks to fix as well. Everything is dried out and cracked. I'm actually surprised I was able to limp it home. But it is still a great project!
 

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Discussion Starter · #7 ·
Got it back together, started up without a hitch. Then the gauges went out. But the misfires went away. Replaced the O2 sensor, but the code came back after I wiped the memory. Runs rough as hell. Any ideas?
 

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Discussion Starter · #11 ·
Sent the PCM in to Neatcomp to be tested. They say it tests fine, and it ran their test car. But the case is so corroded they won't open it to take a look. But they'll sell me a new one! Any better ideas? Beside a grenade?
 
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