Ok I have a 94 ls motor complete swap, can i just remove my civic harness and just use the ls motor harness? or do i have to get the harness conversion

 

What year civic??? EG just add any wires that you need too and plug in the LS engine loom.. EK use the stock civic harness and rework it to fit the LS..

 

From your username it looks likes you have a 97 EX? If so, then no the harness wont work. You've got a OBD-2 harness and the LS engine will be an OBD-1 engine. Also, your harness and ECU I think has the VTEC function and will throw a code and you'll have lose connectors.

Actually, I don't really know. I've never done the swap. Someone will help ya out more.

 

Okay if you have a 97 EX then the swap is relly easy.. Just make the EX harness fit the LS motor extending anything that you may have too... You will have extra wires for VTEC, VTM, KS, etc. Even though it may not look the cleanest i would just leave them i case you ever decide to do LSVTEC or swap motors.. I swapped a GSR into my friend '96 hatch.. it was originally a DX so it made my wiring job a lot more fun.. You got it pretty easy.. Also as you mentioned if you got and OBD1 ECU you'll either have to swap it out for an OBD2a P75 or run on OBD1-2 converter.. Either way will work.. With the OBD2 ECU you'll need to change out the oil pump with a 96+ one so that you can mount a crankshafts speed fluctuation sensor. It may just be easier to get the converter then you only gotta bolt up 1 oxygen sensor too.. Hope this helps