H22 Help, Yet Again!

after i drive for a little bit and it gets warmed up...my D-4 will start blinking...and when i get to a stop light and let off the brake...and go to accelerate...it acts like its in neutral for about 1000-1500 rpms and kicks in to drive and acclerates..

any help would be appreciated VERY much? thank you

Peter

Is your check engine light on? How's your transmission fluid?

yes the check engine light is on due to the engine swap and no port for the o2 sensor. and i JUST got the trans. flushed a few months ago.