sohc ZC into 91 civic si, code 15 ?

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hopps

New Member
Heyas, I have been searching several honda sites for the last few days and it always seems like people allude to it but never completely answer it. Correct me if i'm wrong about anything please

I have a 91' civic si and I a sohc zc I have the engine in, I get fuel, but no spark and a code 15, ignition output or whatever.I replaced the ignitor, cap, rotor on my old dizzy and that didn't fix the problem so I then bought a remanned dizzy off ebay and I still get a code 15 and no spark. I am pretty sure I have all the ground wires connected. With this setup everything basically plug and plays right? I keep finding people talking about switching wires on the dizzy, adding wires to the ecu but I don't know what applies. To this swap, is there anything I am missing? I have not done any splicing etc.

Thanks,
Nate
 
The swap

Most of the time when you swap motors, and you have problems, you just have something connected up wrong, or unplugged. I doubt you have a bad part on the motor. I alway's recommend you use the ecu that goes with the motor also, important. Also the wire harness, and intake manifold, you can avoid lotts of problems if you use all the right parts.

Check the starter wires, for correct connection, also for corrosion, you will be surprised what that green shit does to a wire.

Try to jump the starter with a pair of pliers to make it turn over.
or your battery might be dead.

I Hate Honda's hahaha
 
The motor turns over fine, I am just not getting any spark @ the wire, wires are good I pulled some off my running honda to test it with.

jlicrx: Funny thing, I can't remember which harness i used, I started this swap like 2 years ago and then got busy on a 240 swap and another honda swap and when I came back to this one I can't remember which harness I used...it is the si ecu but from what I have read the sohc zc and the ef si civics were very similiar, If I was using the si harness are there any changes I have to make to it? I am pretty sure that I am using the ZC harness but this zc came out of a swapped crx so like I don't know the history on it either....
 
The motor turns over fine, I am just not getting any spark @ the wire, wires are good I pulled some off my running honda to test it with.

jlicrx: Funny thing, I can't remember which harness i used, I started this swap like 2 years ago and then got busy on a 240 swap and another honda swap and when I came back to this one I can't remember which harness I used...it is the si ecu but from what I have read the sohc zc and the ef si civics were very similiar, If I was using the si harness are there any changes I have to make to it? I am pretty sure that I am using the ZC harness but this zc came out of a swapped crx so like I don't know the history on it either....
was the CRX that the engine came out of the HF model? - the reason i asked about the harness is that the condition you describe is exactly what happens when you try to use the HF harness in the Si car - the HF harness has the wire for the igniter in the driver's side connector at the firewall where the Si harness has the igniter wire in the passenger side connector - the HF connector also has all but one of the fuel injector wires (yellow) in different locations in the driver's side connector - look at the round 8-wire connector next to the resistor box and see if all of the wire colors are matching on both sides of the connector and see if it has a white wire on the engine harness at that connector - if the colors don't match and it has a white wire, it is the HF engine harness and won't work in the Si car without repinning a bunch of wires
 
Ok, thats exactly what it was, both drivers side and passenger side connectors did not match wires with their counterparts. I take it I need an SI engine harness then and that will clean it up ?
 
Ok, thats exactly what it was, both drivers side and passenger side connectors did not match wires with their counterparts. I take it I need an SI engine harness then and that will clean it up ?
Si engine harness will fix it or you can rework the HF harness to make it work, like this:

the wires (except for one) are in different locations in the HF and Si connectors - see picture below

the igniter wire (code 15) is the white wire in the HF harness connector at the driver's side - the igniter wire (white) in the Si harness is in the passenger side connector

the HF engine harness will also have a connector for the EGR valve with 3-wires, yellow, yellow/white and green/white

to make the HF engine harness work with the 89-91 Si chassis harness, first, repin the wires in the 8-pin driver's side HF harness connector so that they match color for color with the Si chassis connector - you will have 2 wires that don't match, one of the yellows (from EGR) and a white (igniter) on the HF connector and black/yellow and dark blue (both from fast idle control valve) on the Si connector - forget these as they won't be used - notice that the HF connector has 2 yellow wires - the yellow wire for injector #4 is the only one that is in the same location on both connectors and is the yellow that is used - next, go to the round 6-pin connector on the passenger side - on the HF harness, find the yellow/white wire from the EGR valve - it should be in the same location as the white igniter wire in the Si chassis harness - at the other end of the yellow/white wire at the EGR valve connector, cut this wire - at the distributor connector, find the white igniter wire - it is the thicker white wire (see attached picture) - cut the white wire - connect the yellow/white (from the 6-pin passenger side connector) that went to the EGR to the white igniter at the distributor connector - make sure that all other wires in both the 6-pin and 14-pin connectors on the passenger side match color for color at both sides of the connectors - should be it
 

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