I have a mazda rx-7 fd3s twin turbo with an apexi ecu and fc commander. Yesterday I was driving at 50mph / 2500 rpm....it would seem the the engine would "die" but the tachometer would shoot up from 2500 rpm to 4000 rpm and the lights on the dash would glow very little as if theres no power in the battery. Upon looking at the fc handset it stated that I have 14.1 volts in the battery ( the alternator was changed last month). If I was to disengage the gears and wait about 2-3 seconds the car would kick back in without me turning the ignition key...as if the ecu has a glitch or there was no fuel getting to the chamber.

 

Hmm, shot in the dark. Leaking windsheild or something else that is causing you to get water into or on pertinent electrical components. (Such as the ecu). Can cause all kinds of electrical phenomena. Also could be something totally different........