93 CIVIC EX won't turn over 2000 rps

[SLTSTRANGE]

I have a 1993 honda civic with a d15b swap. in park and neutral i can rev as high as i want to but put it in drive and 1st gear its ok after that the car wont go over 2000 rpms. It doesn't have a check engine light on. Anyone have any ideas or have had the same problem?

 

[BIGROB90]

first of all is it auto, any mods, have you changed all the fluids and have you reset the ecu

 

[SLTSTRANGE]

yes its auto and i've removed the air from the coolant and cleaned the iacv i disconnected the battery waited till the next day to reconnect it then let it idle for 10 to 15min but when i went to drive it it will not turn enough rms to even change gears

 

[CAFROG]

EDIT: Re-read the first post (correctly this time) If there are no codes.....and its an auto.....maybe its something with the transmission...?

 

[SLTSTRANGE]

no there are no codes both the engine and trans are both new