1sikhatch

my eg hatch came with a 1 wire o2 sensor and i need to put in a 4 wire o2 sensor so i got a wire harness from a ex, can i just use the engine harness or do i need the harness that runs inside the cabin to the ecu also?

MrMike

WHT - WHT/RED wire goes to D14 which is O2 Sensor Input
BLK - ORG/BLK wire goes to A6, which is Heater Control
GRN - GRN/WHT wire goes to D22 which is Sensor Ground
BLK - YEL/BLK wire goes to A25 which is Sensor voltage (you can also splice into the power junction harness at the driver side shock tower harness)

You will need to add in the orange/black wire from the shock tower connector, through the firewall, and to the ECU at A6.

ReDHaTcHyGuy

if u have a ex harness u don't have to add anything for the o2.. they were already in the rest of the harness on my 93 cx.. when i put a z6 in mine i only had to add the vtec wires from the shock tower to the ecu since i used a ex harness as well , if u have a 92 u don't have to wire anything, just plug the ex harness in

1sikhatch

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ReDHaTcHyGuy &raquo;</TD></TR><TR><TD CLASS="quote">if u have a ex harness u don't have to add anything for the o2.. they were already in the rest of the harness on my 93 cx.. when i put a z6 in mine i only had to add the vtec wires from the shock tower to the ecu since i used a ex harness as well , if u have a 92 u don't have to wire anything, just plug the ex harness in</TD></TR></TABLE>

i have a 93 dx, so can i just use the engine harness and not have to wire anything else but the vtec wires?

ReDHaTcHyGuy

yea .. and it sounds like the motor in ur dx was changed out at some time as well as the harness... the dx's came with a 4 wire 02 in the engine harness, but yea all u need to do is plug it in and tap into the strut tower for the vtev wires.. there are 2 blanks in the top plug . u will have to unpin them those are the 2 u need .. i forget off the top of my head which they are and where they pin into the ecu... I think it makes everything look cleaner if you do it this way..since you're just adding to the factory harness

ReDHaTcHyGuy

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 1sikhatch &raquo;</TD></TR><TR><TD CLASS="quote">

i have a 93 dx, so can i just use the engine harness and not have to wire anything else but the vtec wires?</TD></TR></TABLE>

since ur car is a dx .. just outta curiousity look at the plug on the back side where the o2 plugs in just to see if there are 4 wires on the other side... someone may have put in a cx motor and ecu

1sikhatch

theres only 1 wire for the o2 sensor not even a plug, someone cut the plug off and spliced the wire for the 02 so i guess i'll just put in the ex harness and hope my car works like its supposed to now.

Thanks

ReDHaTcHyGuy

u shouldn't have any problems...

j12ball

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by MrMike &raquo;</TD></TR><TR><TD CLASS="quote">WHT - WHT/RED wire goes to D14 which is O2 Sensor Input
BLK - ORG/BLK wire goes to A6, which is Heater Control
GRN - GRN/WHT wire goes to D22 which is Sensor Ground
BLK - YEL/BLK wire goes to A25 which is Sensor voltage (you can also splice into the power junction harness at the driver side shock tower harness)

You will need to add in the orange/black wire from the shock tower connector, through the firewall, and to the ECU at A6. </TD></TR></TABLE>

so these instructions would work if you're using a 92 cx harness? it seems like D22 and A25 are already connected and I would just need to add A6? or do i need to add all 3?

SHG_EasyE

i am very curious about this myself..... i have the gsr engine harness completely intact, that is off the mototr i am using.... so i need to just run one wire to a6 from that plaug in the engine bay? i thouhg tthe was just one wire (heat wire or something like that) that had to go to the ecu... and that would obviously already be connected from the 1 wire setup.... and then the rest would be integrated for poer and ground etc via the gsr engine harness. someone let me know if i am correct pllleasse?? im having a real hard time finding a clear explanation as to what to do. thanks in advance everyone!

ReDHaTcHyGuy

if u have a 92-95 hatch all the wires are already in the ecu harness...what motor are u planning on running?

SHG_EasyE

well its a cx, which is the only one different from the rest, it uses a 1 wire 02 sensor.... idk if that makes a diff with what wires go directly to the ecu. ill be using an obd1 b18c1 and a p28 ecu wich is desighned for a 4 wire setup as well

ReDHaTcHyGuy

the wires from the shock tower to the ecu has everything except vtec .. unless its a 92 , all 92's were pre wired for vtec so u could just plug it in ...

boostedcivicsir

this is the write up i use:

http://www.hybridautomotive.com/tech/o2/#seven

SHG_EasyE

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by boostedcivicsir &raquo;</TD></TR><TR><TD CLASS="quote">this is the write up i use:

http://www.hybridautomotive.com/tech/o2/#seven</TD></TR></TABLE>

thanks alot man that exactly what i needed

boostedcivicsir

n.p.

ReDHaTcHyGuy

that look's like there useing the stock engine harness.. and converting that from 1-4 wire..........if u have a different harness u don't need to do anything

SHG_EasyE

so if im using my gsr engine harness, i dont need to do anything? theres no extra wiring that needs to go back to the ecu?

ReDHaTcHyGuy

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by spoonjdmdc2 &raquo;</TD></TR><TR><TD CLASS="quote">so if im using my gsr engine harness, i dont need to do anything? theres no extra wiring that needs to go back to the ecu?</TD></TR></TABLE>

what year and model are u useing?

SHG_EasyE

ive got a 95 civic cx with a 94 b18c1

j12ball

I just found this how-to over on honda-swap. Its down at the bottom of the page, under the vtec stuff, using katman's vtec ecu diagram. Thought it might be helpful for people. I'm gonna use it this weekend to wire mine.

http://www.hondaswap.com/forum...41608

SHG_EasyE

that really doesnt explain how to switch it from a 1 to 4 wire... because my car has a 1... and my harness and engine have a 4.. but im using a p28 ecu... so what should i use?.. also do i need to run a knock sensor wire if im using the p28 ecu? does it look for a k/s?

j12ball

If you use this diagram telling you what wire is what and combine it with the hondaswap link i gave, you should be able to figure it out. I did it last saturday with those two links. As for the ks, my z6 swap didn't need it, so hopefully you can find your answers for that somewhere. good luck.

http://www.hybridautomotive.com/tech/o2/#seven

SHG_EasyE

ok well im using the gsr engine harness, so al of that is done... so that means i dont have th run any wires to the ecu from the shock towe plug?i am using a p28 ecu - what number of wires does that ecu look for?how many wires were on the 02 sensor on your z6? that uses a p28 right?

1sikhatch

damn i did this and im still getting code 41.