I am not too familiar with a 94 but I am reasonably sure it has a waste spark ignition system which basically is one coil for two cylinders. One plug fires on compression and the other on exhaust. If you blew out one plug then there is no load for that side of the coil and you may have damaged the coil. The coil problem manifests itself as a misfire and resulting engine stumble under moderate load.

 

I may have used the wrong term. The spark plug was physically blown out of the combustion chamber, undamaged, and still attached to the plug wire.

 

When the plug body is not attached to the block it is basically the same as disconnecting the plug wire. When one side of a waste spark coil is not connected it can damage the coil. If the engine was running OK before the plug was blown out it is a reasonable conclusion that maybe the new problem is somehow related. If you have an ohm meter you can measure the resistance across the coil plug connectors and compare to the other coils.

 

Thanks for the tip! I will try that.

 

I Had the same thought about the waste spark, but if it blew out and was laying in the tube, it was most likely still arcing across the electrode and to the tube. The computer may have sensed the problem caused by no compression and resulting mixture difference and be trying to compensate for it. I am not all that familiar with the fuel management's learn and memory system for this specific setup. Might try resetting the computer. I believe you pull the ecm fuse and keep it out for at least 5 seconds. Dennis

 

I have poor electronic troubleshooting skills. Using a multimeter, precisely how will I check the resistance? I would go from the coil plug connection to ground?

 

The secondary winding (high voltage) of each coil is connected to two spark plugs, measure the resistance from one spark plug connector to the other. Do that for each of the 3 coils and compare the readings.
This link provides a very good ignition system tutorial

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All the coils' resistance checked out. I did a compression test, all cylinders were around 190 psi except cyl 2, which was around 155. I also replaced all the spark plugs to no benefit.

 

It appears then you may have a fuel delivery problem, try changing the fuel filter. If that does not fix it you could have a defective fuel pressure regulator.