i have a 96 civic with d16y7 engine with an automatic transmission. at first i thought it was the transmission and it wasnt that because when i leave it in park and rev it up. it lags at like 2000-3500 rpm and after that itll go up and every time i try to rev it. its like that. when i put it in drive. i try to go slowly and give it gas and floor it to see if it revs up but it doesnt even rev up past 2500 rpm. i just drained the auto tranny fluid and put new oil in and then i checked the wires and they had spark and it seems to idle fine. its just that lag and that loss in power

 

check your timing, and maybe your o2 sensor, the first one, not second one.