i have a 96 hx that i just got and the guy who had it b4 me changed it 2 5speed cuz it was auto but never switched the ecu soo it had a check engine light and it idled and he told me it was because of the ecu....soo i went to the junkyard and got a 98 civic ex ecu thinking it would work and it just made it worse...soo my question is what ecu do i have to use....do i have 2 get a 5speed hx ecu or can i just use any other 1....oh and the guy that owned it b4 told me just to get a p28...do you think i should just do that??? some body let me know cuz im really stuck on this...thanx

 

if you get the p28, you will need an OBD2 to OBD1 conversion harness.
was the engine swapped too?
hx uses different ecu than ex

 

IF you still have the D16Y5...
get a 5-speed P2N.
P2N-A21 = 96
P2N-A22 = 97
P2N-A31 = 98
P2N-A32 = 99-00
P2N-A33 = 99-00 (replaced the A32)
all are OBD2a, so they will plug right into your car.
(and before anyone else says it, the HX didn't switch to OBD2b for 99-00)

any other ECU else will require converting to a 4-wire primary O2 and tuning it to make it run right. (the OBD1 P07 runs the 5-wire O2 but is for a 1.5L engine vs the HX's 1.6L engine, and will never pass emissions testing since it's OBD1)

 

i tried a couple ecu's but none of them were working right...i got a 96 hx manual ecu and it was fine it just idles high and then i went to a performance shop and the guy told me 2 just go with the p28 and the obd2 obd1 jumper harness so i think i'm just gonna do that