somtimes Back fires through intake, has a hard time starting due to kickback, will be so back motor will stop turning over. no codes injector flow test passed pulled plugs to check for poss. hydrolock pulled intake to visual inspect injectors for leakage.any ideas? I have IDS cababilities

1990 F-250 5.8L A/T Every morning it will start right up, then every time after that it cranks a little slower each time, about the end of the day (6th time starting) it will just not even turn over for like a full second, then it cranks slowly then starts. Next morning, cranks fast and starts...