Unphzd

I am hearing many different answers from many different people. i currently have a gsr wiring harness that came with my 97 civic ek that was used in the civic connected to a gsr engine with a p72 ecu with a obd 2 to obd1 conversion harness on the ecu. steve from hmotors is saying i can use the gsr wiring harness the guy used for my d15b and have some left over wires. some are saying im gonna need to buy a d15 engine wiring harness. i am putting in a jdm 97 d15b vtec into my 97 ek.

whos saying the truth? or will i need to buy a new wiring harness? and if so what wiring harness can i use?

my ecu is the p2j

Thanks for the help

HondaPartsHero

Which D15B is it? VTEC, Non VTEC? OBD1, OBD2? You should be fine with the GSR harness. You'll have some extra plugs left over if you run an OBD1 ECU (CFK) and you'll need to swap over to OBD1 style plugs on a few sensors (injectors, distributor, alternator).

97-Civic-Ex

What is the rest of your ECU code? I.E. P2J-003 or P2J-011 or any other such P2J? Also, What is the extension of the P27 ECU,... i.e. P72-A01? There where 2 different types of OBDII wire harnesses which came with the respective OBDII ECUs. For the most part and OBDIIa wire harnes will work with most OBDIIa ecu/motor applications give or take a few wires,... like wise OBDIIb wire harnesses will work for most OBDIIb ECUs/motors. But they will not work without major modifications if you cross the 2. So knowing what ECU (complete number) the car used before and what ECU (complete number) you wish to use now will help identify if you can use them.

So more info is needed.

94EG8

Its unlikely that you have a GS-R harness, as they don't fit in a '96 - '00 civic, its most likely a modified civic harness. And yes it will work, you may have to make some modifications to it, but it will work.

Unphzd

its a jdm d15b vtec. Using a p2j ecu. 003 is continued after got it from h motors for a manual. what will i have to modify on it? my friend said the ecu plugs? will that be hard or easy? im gonna be working on this tomorrow afternoon at 12 soo if i could get some replies tonight that would be great!

97-Civic-Ex

Let me try this again. You need to tell us what ECU was previouly used to see if it is an OBDIIa or OBDIIb. We got only have of the info,... P2J-003 is an OBDIIa ECU, so for it to be plug and play,(with minor wires to add) your previous ECU P72 must also be OBDIIa. So what is that ECU P72-???

Unphzd

i am currently not at home but from what i remember from the conversion harness ports it had had obd2a ports http://www.hondata.com/techecuid.html if whats on this picture is right.

97-Civic-Ex

ok, then you have as a plug and play harness as you can have. From my research you will be missing 1 vtec wire, and the egr wires(not sure how many). You should read this entire thread to understand how your computer should work and what your motor expects.
http://www.d-series.org/forums/engin...e-control.html

However, your harness as it stands should make your motor run,... but you will have a check engine light for the missing wires/sensors.

Unphzd

soo i should be able to plug it in and will work? i just need to rewire vtec? and what else? thanks for the help too i was soo worried i wouldnt be able to work on it tomorrow because i wouldnt have a wiring harness. should i just zip tie the extra plugs?

97-Civic-Ex

it shud turn on and run,... it probably will not run well though. I don't think you will have any extra plugs,... rather you will have extra wires within the plugs,.. and missing wires where they should be(namely the ones i pointed out). Here are a couple wires to hook up to your ECU for the extra Vtec:

http://www.d-series.org/forums/engin...ml#post2089613

Unphzd

ohh mmk by not run well what do you mean? will it ruin my engine? ohhh ook do you know where i can get the wiring diagram for this? will it be ok if i wire vtec later? and just run the motor without vtec.

97-Civic-Ex

Ok, well all the info i am posting is purely from research and not from personal experience. Thats why I posted those links. That 1 thread has the most info on the d15b and the ECUs, so read it completely. The last few posts has the bently for that specific motor, so I suggest you go there for your wiring diagrams.
About it not runing right, its because you will not be engaging the vtec the way the ECU expects it to. So you might be in 12Valve mode when your ECU wants it to be in 16Valve mode. The rewiring of the vtec shouldn't take you too long if you take some time to figure out what wire goes where. The vtec solenoid only has a red wire and a green one. Look it up and see where they go. Aside from that, I don't think your wiring harness has the egr signals. Look those up too.

Unphzd

ohh ok thanks for all this info your a life saver! sorry if i ask too many questions im a noob :\ and really bad at research. without adding the other wires will it pass emissions here in washington state you think? or will i need to add those to make it pass? ohh ok ill make sure i look into those threads tonight! dang 12 page thread.. but its worth it haha. ohh last question do you know where the catalytic converter go on the d15b? cuz it usually goes right after the exhaust manifold but i think my car goes straight from the manifold to the tail pipe.

97-Civic-Ex

well im in cali, so I am not familiar with washington emissions. However, if they test for check engine lights, you will not pass. As for the CAT, it resides right on the manifold, kind of like the CRX HF and the Civic VX. It has to be close to the manifold due to the lean burn mode. It requires m ore heat to bring down the higher NOX it emmits. So if the motor you have didn't come with the cat, you might be emitting more emissions if you put it on with the cat under the passanger compartment(like my EX).

Unphzd

ohh here are some pics btw of the ecus,
http://sphotos.ak.fbcdn.net/hphotos-..._5760703_n.jpg
p72-a01

http://sphotos.ak.fbcdn.net/hphotos-..._7526029_n.jpg
p2j-003

should i buy the new exhaust manifold with the cat then? or just have a cat welded on the pipe?

hmm dang.. this is tricky.

how long do you think till i get the right wiring on for the check engine light to disappear cuz i have to pass emissions for me to get my title on this car... they wont transfer it over to me which i find ridiculous...

94EG8

You wont pass emissions with the setup period. JDM ECUs do not communicate with a scan tool. There was a really good thread on this swap just recently but I can't seem to find it.

Unphzd

ohh what?? really? what will i need to do to pass emissions then?? would it worked if i plugged in the p27 ecu then?

i still dont know how to get my cat in... haha

customy8

I have a few threads on D-series.org, Im of course Customy8. The p2j ecu in a 97 ex will require the addition of the egr 3 wire conector for egr lift, and 2 wires for the egr vacuum solenoid, and you'll have to de-pin and remove 3 wire's from the o2 sensor, 2 from the vtec pressure switch, not needed on a jdm ecu. And add the lean burn light if wanted. There will not be connection to a scan tool, therefore failed emission, but the jumper wires on the pass side still work for checking codes. There is a CN2 spot in the ecu that may be able to be linked to the dataloggers for obd1 ecu's for general voltage and information from the ecu.

customy8

you will need a p2p ecu for emisions reasons, im boosted on my d15b with larger injectors and an obd1 ecu, and when emisions rolls around i simply swap in the stock injectors, open the wastegate, connect the p2p ecu and drive for about an hour , then roll in and pass emisions, in my opinion, a obd1 p72 spec chipped/ hondata s300 ecu is the best for the engine here, this way you still maintain all your vehicles stock wireing with the addition of a extra wire ran into the engine bay to a relay then to the 1st vtec solenoid.