Civic EG

Hey guys im trying to installe my gsr obd1 but unfortunately i cant get the wiring properly. Im using the si harness and the p72. What are the cables i need to take out or put in. I was trying to look at the sticky post in this forum but it says for p28 and i cant even understand it. Could you help me pls.

I don't know why it says P28. It's the same for all OBD1 ECUs. That is what you need to use.

What don't you understand? Go to the junkyard and cut off any OBD1 Honda ECU harness. Just one of the three plug connectors will suffice. Get as much wire length as you can. Pry open the holders on the connector and de-pin several wires using a paper clip. Pop those into your harness in the appropriate locations and extend the wires so you can wire them up to the sensors/solenoids on your engine.

It's cake.

suspendedHatch wrote:I don't know why it says P28. It's the same for all OBD1 ECUs. That is what you need to use.

What don't you understand? Go to the junkyard and cut off any OBD1 Honda ECU harness. Just one of the three plug connectors will suffice. Get as much wire length as you can. Pry open the holders on the connector and de-pin several wires using a paper clip. Pop those into your harness in the appropriate locations and extend the wires so you can wire them up to the sensors/solenoids on your engine.

It's cake.

ok perfect as long as ALL obd1 ecus are the same im good. I thought that p28 and p72 were different hence different names.

So yeah the engine came with harness, however i read that i could use my own harness since i got an Si which already has vtec. I believe all i needed to do was connect 2 wires at D3 and A17 for Knock sensor and IAB respectively. This should be right i believe.

On th eother hand, according to the picture i just need to connect A20 (EVAP Purge Solenoid) and A17 but i've read that i need D3 too.

As the explanation says in the picture only knock sensor and secondary butterflies need to be wired in. but i dont know whcih one is the later one A20 or A17.