Wiring Harness Question

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hey guys take it easy on me im a newbie :) this is the situation...... i have a uk civic lsi wich has a d15 (obd):

im going to be puttin a obd2 b18c motor in it....but im going to be using a obd1 p72 ecu....
i've been told to use the harness off the d15 but then i'd have to wire in vtec and the 2 other injectors ect.. but my question is, can i jus use the b18 obd2 harness and buy a OBD2 - OBD1 conversion harness jumper wire thing?

surly this would be simplier than wiring the vtec and other 2 injectors up?

plzz help


Looking at the pic you posted, you don't need to wire and extra injectors. You'd have to wire vtec anyway, along with IABs. That harness is just so you can run the OBD II ECU in an OBD I car.

You should be able to use the B18C's engine harness, and just run the wires from the canon plugs to the ECU.
An Si harness would be more or less the same as a GSR, except you'd have to extend a few wires on the Si. Either way, unless your car is a 92, you're going to have to run wires from the strut tower plugs to your ECU for VTEC solenoid, and VTEC oil psi. Even if your car is a 92 (92's in-car harnesses are pre-wired for VTEC), you're going to have to run wires for a knock sensor and the IAB's.

So in short:

1. Use the GSR harness.
2. If your car is a 92, plug in the GSR harness and run wires for your knock sensor and IAB's.
3. If your car is a 93-95, plug in the GSR harness and run wires for VTEC solenoid, VTEC oil psi switch, knock sensor, and IAB's.
i jus fould out tho that my d15 is infact obd0 so that harness is usless anyway. i've been told the easy thing to do its get a wiring harness off of a B16 OBD1 eg hatch.... plug it all in.... run the wires for the vtec and the butterfly valves and its sorted?

i've been told the B16 OBD1 out of an eg hatch would be the easyest to work with
Even if your d15 IS obd0, your car isn't. That car is a 92-95 Hatch. 92-95=obd1. Refer to my above post.

A B16 OBD1 harness is going to be the exact same thing as a GSR harness. Exact. READ, dude. Geez.
sorry if im gettin anoying guys, this has really confused me, different ppl keep telling me to do different things ect.. so plz bear with me lol


Originally posted by APEXi@Jun 7 2005, 02:09 AM
ok, my GSR harness is obd2 rite? so... it aint gonna plug into my obd1 p72 ecu is it?
[post=508763]Quoted post[/post]​

Ok, nice and slow...

The OBD II GSR harness plugs into your car in the engine bay, in what are refered to sometimes as canon plugs, or shock tower plugs, they are on either side if the engine bay near the battery and same place on the other side. The GSR engine harness whether it's OBD I or OBD II will plug right into these plugs.

You ECU plugs into the cabin harness, and is located under the carpet, under the passengerside just past the kickpanel. Completely different than the engine bay harness.

So, you use the GSR's engine harness, plug it into your engine bay plugs, then you take the OBD I->OBD II ECU harness, and plug it into your cabin harness, then plug your ECU to that. Then you're going to have to add whatever wiring the Civic is missing to run the GSR motor, vtec, knock, IABs, etc...

Did someone swap the D15B into there? If not, it is OBD I.
The D15 comes in eg's over here, eg4's.

as i'll be useing the gsr wiring harness then dus this mean im still gonna have to wire in the 2 other injectors?

again thanx for the help
here is the wiring harness:

on closer inspection i found that the harness is ether been damaged or has been changed. im talkin about the plugs near the fuse box in pic 1.
here is a closer look:


the wires that have been cut are:

dus and 1 have any ideas y these have been cut or changed? anything to do with vtec, knock, IABs, etc...? what should i do? solder them back to gether or have they been cut for a deasion ya think?

soz about big pics :redface:


The car in the picture you posted has four injectors, no, you don't need to wire more.

Is that the cabin harness? Looks like it, ditch that POS, use the one that's in your car now, and use the engine harness from the GSR, if you don't have the engine harness, use yours, and add the needed wires. Or throw what you have in the back of your hatch and drive to Germany, and I'll do it for ya :)
lol, the d15 in the car at the moment is only duel point injection, not multipoint, so wot wires will have to be added got the d15 harness?
Originally posted by 92b16vx@Jun 7 2005, 03:49 PM
The car in the picture you posted has four injectors, no, you don't need to wire more.

No it doesn't...lol....look at his intake manifold. I didn't notice until just now. Something isn't right....as far as I know Honda didn't make dual point ANYTHING after 91...