Car is a 99 DX Coupe
Motor is OBD1 GS-R
ECU is chipped p28/Neptuned (OBD2 to OBD1 ECU harness connected to it)

ALTERNATOR
I have already hardwired my alternator plug from my old OBD1 harness (which worked perfectly in my EH2 when the motor was in there) onto the OBD2 harness. All four colored wires matched up perfectly. I should be fine right?

DIZZY
I've searched, and people say you can just "repin" the OBD1 dizzy to plug into the OBD2 harness. I was wondering, can I just hard wire the dizzy plugs from my OBD1 harness onto the OBD2 harness? I've taken some pics and labeled each wire in the pics if anybody could take the time to show me how:











I've tried following this how-to, but if you can tell...the instructions have a "dark blue" and a "light blue" that I don't have. I have a regular "blue" but no "dark blue" (unless im confusing the solid "black" with the "dark blue" but it looks like black to me so hah)



EDIT: I did find this on the rywire website. I would just like to skip this extra couple of plugs and plug up my old plugs to the new harness. I just need to know the colors:



VTEC
My next question is about the vtec plugs on my OBD1 harness vs OBD2 harness. Am I able to somehow re-wire these two plugs so that my VTEC works? Sorry such a n00b!










IACV
I also hard wired the IACV plug (2 wire) from OBD1 harness to OBD2 harness (3 wire) according to the http://www.ff-squad.com website. (awesome help that site btw!) the only part i was a lil confused about was about repining the B plug like this when I am using the OBD2-OBD1 conversion harness. Do I still repin this like the instructions say?




If anybody can help, I would greatly appreciate it. I know people have probably made this work before. I plan to resleeve the entire harness with new material/tape (after I get all the hard connections figured out, wire tuck FTW!) so if I need to take this thing apart completely, I'm going to do it anyway.

I understand Peter at Rywire can do all of this for me for $165 (minus a lil HT discount), but I don't have money to throw around and I kinda wanna learn something new.

Thanks in advance!
Dinko

 

The two mystery plugs that you are talking about are for the O2 sensors. the obd1 harness only had one o2 sensor and obd2 had two. not sure which plug is the upstream and which is the downstream but Im 99.9999999999% sure thats what there for.

as for the alt. wires you should be fine as long as you matched wires. and yes, you can splice the obd1 dizzy harness onto the obd2 harness. all the wires are the same color. Ive got a 95 si motor in my 97 civic and I did the same thing. just put the plug on the harness.

 

thanks for the write up, i was JUST about to do one....instead of looking at pictures i had to read wire diagrams to splice together the dizzy plugs and they work really well.

also, for the grey vtec plug, i just got needle nose pliers and ripped off the white plastic caps from both ends and that will work fine...no splicing required

i also didnt have to depin any ecu plug and vtec still kicks in

 

this is the plug i can't get into the jumper harness.



Previous owner said jumper harness is obd2B --> obd1. Can someone verify this by looking at these plugs? My dizzy plug is the 8pin design if that matters...how do i tell if i need obd2a or obd2b --> obd1 jumper harness ?

i should be getting some help on the dizzy rewiring, then just need to throw in the 3 vtec wires, and rewire the injector clips. that should be it i hope.

i knew the wiring on this car was gonna be a headache

 

i belive that green plug does not plug into that it. There should be a gray plug next to your kick panel and the gray one should plug into the jumper. There will be a place to plug that green one next to the gray one in your kick panel.

 

I'm assuming your state doesn't care about inspections for OBD2 vehicles?