its your car telling u in morse code... SWAP ME... SWAP ME... SWAP ME...
on the real tho, are your motor mounts good?
i blew out my motor mounts once and from the tranny/engine lifting, i cracked the soleniod ontop of the tranny (under the batterytray) it cracked from hittin the tray and gave me that problem (not saying this is ur solution but something to look into)
ps: everytime my tranny blew (3xs) i never got a blinking d4 light, it would slip a few times, throw the CEL's and then quit on me.
the D4 light most of the time points to a solenoid