2000 3,8 impala misfire

[tseimpala]

I have a 2000 3.8 with 215,000 miles ( yes that is correct origanal motor)
I have been recieving a 304 code (cylinder #4 missfire) I had to change the upper and lower intake manifold gaskets and while doing this i sent the injectors out ot be cleaned, I replaced them in no special order and now i am recieving a 302 (cylinder #2 missfire)

I have changed all plugs, wires, coils, with the price of injectors at $150 each i would like to see if any body else has had the same problem or might be able to guide me in the proper direction.
Looking to get 300,000

[richtazz]

I would bet that the injector that came out of cylinder 4 (causing P0304) was put back in cylinder 2 (now causing P0302), so that injector is most likely the culprit.

[phewop118]

The injector would also be my best guess. Are those original injectors? Some 3800 Series II's have been known to have injector troubles.