I have a Dinan piggyback and it seems like every couple of weeks the transmission shift logic will randomly get confused and go into limp mode on pulls. I've been able to replicate this while testing it in various modes. It doesn't seem to occur when im in manual shift so I don't think it's fuel cut related. It happens literally right as the shift logic tries to downshift. It has this weird stutter like its misfiring which is what the CEL ends up showing. I've replaced plugs but not wires. It doesn't do it all the time though so it's making me think it's potentially the piggyback. Car throws the common "Drivetrain malfunction" which goes away after re-ignition. I'm not noticing that the transmission behaves strangely under normal driving. Shifts are completely fine and smooth and it manually down shifts without any issues.