hey im trying to wire my ls into my 91 si hatch. i have obd1 ls with the obd1 ecu and jumper harness. the engine harness connectors dont match the ones in the car. what do i need for them to connect?

 

Unless you want to deal with a wiring NIGHTMARE - use your factory harness and adapt it as necessary. Everything you need to know is in this link...

https://honda-tech.com/forums/honda-crx-ef-civic-1988-1991-3/88-91-crx-ef-civic-frequently-asked-questions-faqs-1508680/

 

Use the si harness with the jumper. should plug n play. My first swap was a ls used factory
wirering and I even used the d series dizzy and ecu.

 

Ya I found out last night I need the si harness and obd0 ls dizzy. And pr4 ecu. How do I convert my obd1 or 2 dizzy (have both) to obd0 so i dont have to buy another one?

 

You sell it and buy another one.

 

you can not convert obd1 or 2 to obd0 i had the same issue and the obd0 distributor runs the injectors where as the obd1 and do not so you will have to get a harness to distributor jumper and use the factory obd0 harness

all in all

obd0 to obd1 ecu jumper

obd0 to obd1 distributor jumper

obd1 ecu

obd1 distributor

you have to match the ecu to the distributor

 

So the car came with the ecu jumper. But it had lsv in it, the kid blew it up and did an ls swap. So can I still use the jumper with my odb1 p75 instead of buying a pr4? Or will the favt he ran vtec on it before make it not work for the ls?

 

Use the obd1 jumper for the ecu and convert the injectors and distributor plugs on your si engine harness to obd1 spec. Also need to add a 4 wire o2 sensor and your done.

 

you can use the obd 0 injectors you just gotta trim the plastic on the inside

 

u need
obd0 to obd1 dizzy jumper harness
if ur running the obd1 alternator then u need the obd0 to obd1 harness for that
and use crx si injectors ( i dont know what the guy above is talking bout mine fit perfectly)

use rywire.com for the harnesses. great products

 

should be able to use ur crx engine harness
the only problems u should have is dizzy/alt and injectors

 

You don't need to do anything to run an ibd1 alternator on your car. Obd0 and obd1 alternators are the same.

As for the previous guy, he is correct about fitting obd0 injector plugs on obd1 injectors. There are 2 small tabs that need to be trimmed on the plugs to fit into obd1 injectors. OP, if you do run obd1 injectors make sure to also do a resistor box delete.

 

u are correct by bad i was swaping a b20 in a crx witch came with the obd2 alt.

delsol92 said u have to trim obd0 injectors which is wrong if he is using his stock ef harness. the easiest way for me was to get obd0 si injectors which i didnt delete the resistor box and didnt have to rewire the the plugs to obd1 or like u said i guess u could trim them

 

meant to say you have to trim them if you use obd1 i didnt notice that i typed a 0 instead of a 1

 

Yea I'm doing the same to my 91, si hatch and my problem is that it won't rev past 3000, and I don't know what to do or chek, any one know??

 

You can also use rywire.com to get any jumpers you may need. I got their OBD0 harness to OBD1 ecu, injector jumpers, and dizzy jumper.