I have a 93 CX Hatchback. Just swapped a D16z6. I'm a bit confused about the wiring. I know I have to run the wires for vtec to the ecu and wire a 4 wire O2. Mine has a 1 Wire O2. Does the EX Harness take care of all the O2 wiring or do I need to run wires directly to the ECU for the O2 sensor?

So with the EX harness I just have to run two vtec wires to the ECU at D6 and A4 is this correct?

93 CX Chassis, 95 EX D16z6 engine and Harness. P28 ECU.

 

If it was a 92 you would be good with the EX/Si harness, but otherwise use your harness and you'll need to run the wiring for VTEC and the additional 3 wires for your O2 from the sensor directly to the ECU. Here's a diagram from my site, also check out my signature below if you need the wiring:

 

for some reason im thinking back when i put a z6 into my old 93 cx i only had to add the vtec wires from the shock tower to the ecu, i think 92-93 already had the 4 wire 02 wires from the shock tower so u just have to plug the ex harness ... 92's were also prewired for vtec so all you had to do was plug the ex harness in

 

yea i searched quick, all 92-95 civics are pre wired for a 4 wire o2 from the shock tower to the ecu, so if you use a ex harness you dont have to add anything for the o2 just the 2 vtec wires.. you can pin them into the plug at the shock tower to keep a factory look.. thats what i did when i had mine...

here a direct link to the image that is alittle bigger if u cant read it all

http://www.ff-squad.com/tech/wiring/...ktowerplug.jpg

 

That's what I was hoping. Thanks

So i just need to wire D6 and A4 it looks like then?

 

Yup, two wires and your good to go. If you wanted to, you could only add the one wire for VTEC solenoid and bypass the VTEC pressre switch at or in the ECU. Of course that might be more of a pain.

I've got a JDM B18C in my 94 CX and I only had to run 1 wire down to the ECU. My chipped P28 had the VTEC pressure switch disabled inside it.

 

So I got everything wired up at D6 and A4 but now its throwing a check engine light. The light turns on about 3 seconds after I start the car. Can anybody show me where to plug the paperclip in to check the code?

 

https://honda-tech.com/forums/honda-civic-del-sol-1992-2000-1/how-pull-cel-d4-srs-abs-codes-code-lists-1901557/

 

Thanks for all the help guys. I got everything worked out today. I was having trouble finding the CEL plug. I was looking for a grey one but it was blue and tucked away pretty good.

Checked the CEL and it was throwing code 41. I remember reading that was an O2 problem. I am stupid as ****. I forgot to plug in my O2 lol.

So I can confirm that a CX chassis is prewired for a 4 wire O2 and all I had to do was use the Z6 harness and run two wires for vtec. I depinned some from a junk yard motor and soldered them into the factory shock tower plug. It worked out really well and looks legit.

Some say you cant feel SOHC vtec so I didnt know what to expect. But I can tell you from driving around without vtec for a week I can definatly tell its there. 2nd gear at 45MPH I feel it kick in gets a little louder. Not as loud or as hard as my friends stock GSR with CAI. Thats the only comparison I have.

This car rips. Now compared to some of yours maybe not. But I had a D15b8 before and now I got this Z6 with header, exhaust and CAI. It feels really strong in my hatchback. I'm getting excited now to put my turbo on. Its sitting in my garage just need a few more pieces.

 

Are you still running the CX transmission? If so, ditch that $h!t. With an Si tranny, you will probably notice a greater performance gain than the motor swap alone.

 

No I got the trannyt hat came with the Z6 motor. Its 95 EX Trans.

 

Enjoy...