Guys will new Yank Converters
Misfire detect comes from crank sensor irregularity.
This can be real misfires, it can be imbalance in the
rotating assembly, or it can be too much torque ripple
against a too-light flywheel mass.
Aftermarket converters as a minimum will give you
the lighter mass and magnify anything else you've got
going on. They may or may not add imbalance to the
crank.They will for sure make any internal unevenness
show more plainly and there's your possibility of misfire
detect (false, but still).
My old TCI was pretty well behaved for this. TCI spin
balances 100%, even the cheap Streetfighter. My
Fuddle needed misfire detection killed to lock. Fuddle
only measures tolerances and doesn't do dynamic
balancing.
Other manufacturers, I have not seen declare one
way or the other. But tell you what, if I buy another
converter it will for sure be spun balanced. Don't
care who, but anybody who wanted my business
would have to step up to that. Along with all the
other demands that I have built into mine now.

I have seen many things that will make the trans lock and unlock the converter and this is one cause that is overlooked often.


Many times that's due to misfire counts being on the high side. Yank is good stuff, had a few of their converters and would buy again.
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