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Super Secret Area - Dead Ahead!
If you have X as your shoot button, yes.  Otherwise you'll need to use your shoot button.  That's only the start, though, and not the IBJ itself.  That code only lays the first two bombs.  After that you just need to press X again, and then wait the correct number of frames (48, maybe?), press X again, and repeat.  There is no set IBJ code, because the move itself has two different timings: one to start the move, and then one to continue the actual IBJ.

I'm sorry if you're not getting it, but there's nothing wrong with the codes - but they only START the IBJ, which is laying a bomb, laying another as it explodes, and then you'll jump up, and land back on the floor.  You need to manually lay all bombs after that, because there's no need for a code.