that was going to be my question also.. you said you had the black box, but in the mods list you mention the missing link... which one do you have? if both then take out the black box.
as far as your missfire, take out the plugs and wires and check for water could be as simple as that like RxR said.

-97 GS (First project, 299 whp)(sold)
- 97 RS 2.6 last numbers: 306hp, 352tq @16psi (Dead, parted out)
- 99 GS OZ, Hahn Kit, 56k miles (Sold)
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- 00 Nissan Maxima GLE (Daily Driver)
- 02 Audi A4 1.8T Quattro