ka24de problems

[ecopp1991]

ok so i bought this car over the summer and after buying it and getting it home i realized that the motor was junk but i only paid for the shell so it was all good. so i picked up a motor from a junkyard and it was mint..
me and a couple friends swapped it into the car. i decided to put an xcessive intake manifold on it but for some reason i couldnt get it going so i put the stock back on last weekend.
i started it up and it started then started revving very strange going from 400 rpm to 2g to 500 to 1500 then to 200 then shot up to 4g and just about red lined before i shut it off.
so i checked it out and realized that i had a vacuum leak and fixed it and went to start it up again and it just cranked and kept turning and turning but wouldnt turn over so i turned the key back to the off position and it backfired and shot smoke outta the 4th injector. tried again and the same thing, and so on..

we tried checking the plugs and fuel, and the spark plug wires in the right order. so im not sure what to do next and am in some serious need for help

thanks!

[MidwestMyriad]

First off would suggest changing the injector if smoke was coming out of it.