I just installed a jdm H23a vtec obd2 into a 93 prelude obd 1 that had a h23a1 non-vtech using the p14 ecu. the motor fires up but having difficults with the vacuum hoses of the intake because the intake was different on the h23a1 i had. the motor runs but between 1200 and 1600 rpms the motor revs up and down. what do i need to due. the jdm has the map sensor on the intake while the H23a1 has it on the firewall with vacuum hoses going to it. if i get a p28 chiped for the jdm solve my problems or is their some other way to do this

 

i had the same prob in my b16 it ended up being that i needed a y splitter and a few caps to plug off on the back of the intake and the vaacuum lines can also be y split to the intake. find out which are vaacuum and which are exhaust. run the engine plug one see if it makes a diff. do that to all of them just be sure to not plug ones that need to be left open and vica versa. just an idea. tryin to help i went through it and it was just a littlt open vacuum line that was very hard to see.