Looks like the shop has not finished with your vehicle. Maybe they messed up some of the connections when the engine was transplanted?

Well, 104 misfires are 1 of 3 things. (leaving our the potential for a flywheel as it ran fine for awhile)

coils
wires and tips
engine harness.


BTW, the 210.055 had harness problems as well. I've replaced a few for misfire that when opened up at the coil connectors were as bad as some of the 94's.


104's will damn near run forever with some care.



Joe

Maybe some of the sensor connectors were incorrectly installed. This happened to a guy I met one time. He bought a Volvo 850T that had an engine replaced with one from a junkyard, excuse me, Automotice Recycler. It was setting codes left and right. He finally decided to check all the engine wiring harness connections and found several were plugged into the wrong place. Once he fixed that, the car ran great. No more codes.