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ch1873857

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Discussion starter · #1 ·
So i started with the wiring last night on the harness. i took the last 3 plugs of the CA harness and cut the 2 plugs off my KA harness and started connecting and soldering wires.

Question 1: For the o2 sensor there is one brown wire coming out of the CA harness and 2 that are coming out of the plug. Do I connect the 2 browns in the plug to the 1 brown in the harness? The write-up said Any 12 volt switch, I didnt know what that meant im not a wiring guy.

Question 2: It said you only needed 2 plugs on the end of the harness, the third was not used. The one with 2 blue wires. do you just cut the plug off and tape the wires up or do they actually go somewhere.

Question 3: After soldering, i was left with 2 wires minus the browns for o2 and the 2 in the plug i didnt need. Im pretty sure one was blue/white stripe and the other was just plain Blue(maybe a dark blue or purple) im sort of color blind but i can still tell that 2 wires are the same or different.

Oh and one last thing. on the CA plug the big one of the two and in the harness was a few wires taped together in gray tape. one big white, one big black that didnt go to anything and one small black. there was no white wires in the KA plug so i just taped the black and white back up and soldered the small black to the small black in the KA plug. do i need to go back and fix?
 
#3 ·
ch1873857 said:
So i started with the wiring last night on the harness. i took the last 3 plugs of the CA harness and cut the 2 plugs off my KA harness and started connecting and soldering wires.

Question 1: For the o2 sensor there is one brown wire coming out of the CA harness and 2 that are coming out of the plug. Do I connect the 2 browns in the plug to the 1 brown in the harness? The write-up said Any 12 volt switch, I didnt know what that meant im not a wiring guy.

Question 2: It said you only needed 2 plugs on the end of the harness, the third was not used. The one with 2 blue wires. do you just cut the plug off and tape the wires up or do they actually go somewhere.

Question 3: After soldering, i was left with 2 wires minus the browns for o2 and the 2 in the plug i didnt need. Im pretty sure one was blue/white stripe and the other was just plain Blue(maybe a dark blue or purple) im sort of color blind but i can still tell that 2 wires are the same or different.

Oh and one last thing. on the CA plug the big one of the two and in the harness was a few wires taped together in gray tape. one big white, one big black that didnt go to anything and one small black. there was no white wires in the KA plug so i just taped the black and white back up and soldered the small black to the small black in the KA plug. do i need to go back and fix?
Click to expand...
question 1: For your 02 just connect the brown wire from the harness to the outer brown wire from the plug.

question 2: you dont need those wires. you can just cut and tape them or just tape up the plug entirely.

question 3: If those are indeed the colors of the wires you dont need them just make sure you tape them up.

and for your last question if the big white wire was a shielded wire then just use that wire for you knock sensor since it goes to pin 23 of your ecu. and if i remember correctly the small black was spliced into the shielded portion of the big white wire. if so then just resplice it back. and as for the other big wire was it the big Black/Red wire? if so that gets spliced with the Blue/Red from the harness and Black/Red wire from the KA plug side.
hope this helps.
 
Discussion starter · #4 ·
wow thanks man. what did mean by the outer wire? which of the 2?
ok. you lost me on the last part, whats ashielded wire? i was wondering why they didnt say anything about it. im pretty sure the small black went into the plug and the big one was all black. could you explain the knock sensor more. on second thought the big black didnt have any insulated so maybe where spliced together..should i splice them?
 
#6 ·
A shielded wire has fine wire and some insulation wrapped arround it. The fine wire is grounded to the chasis or ecu. It keeps static interference down throughout the harness. This is in general. I've never even seen a ca18, so maybe he is talking about some wire that has black heat shielding arround it... This could be the case, and if your wire is cut it could have fallen off quite easilly.
 
#7 ·
sorry i was real busy the last couple of days. if you look under the intake manifold on the CA there should be a sensor under it connected to the block. that would be your knock sensor. your engine may not run right without it hooked up. if your motor set came with the CA lower harness then the plug for the knock sensor would be on that. alot of people just use the ka lower harness when they do the swap, but there is no knock sensor plug availible on the ka lower harness. So just cut off the plug from the ca harness and splice it into the wire that goes into pin 23 on the ecu. ill get some pics for you by the end of the day.
 
#8 · (Edited)
ok got some pics for ya. :)

first is the brown wire for the 02 sensor. Just splice the brown wire from the CA harness into this wire from the KA plug.
Image


Here's a pic of the knock sensor location under the intake manifold.
Image


A pics of what the knock sensor plug looks like. once again use shielded wire for the knock sensor.
Image



Pic of a shielded wire with the outer layer of insulation removed. The shielded portion is actual made up of a bunch of little wires that are wrap around rubber insulation below it.
Image


Here's a pic of the what wire looks like on the inside. Under the white insulation is the actual wire itself. basically it made up of 4 layers. Outer insulation, shield, inner insulation, and the actual wire.
Image


Please dont pay any attention to the plug itself. I took this pic before I cut the plug off and spliced in the KA plugs. This is the white wire you need to wire the knock sensor to.
Image



Once again pay no attention to the plug pictured. Splice the shielded portion of the knock sensor wire to this black wire. The shield portion stops just a bit before it gets to the knock sensor plug.
Image



A little ways down the line closer to the ecu the black and white wires from the last 2 pics gets spliced back into a shielded wire and then split up again into 2 wires right before they go into the ecu. The white on goes to ecu pin 23, and the black one goes to a pin on the ecu too but I cant remember which pin. The black is just a ground so you should be fine.

Sorry If this was a bit longwinded but trying to make sure you get your ca running right. Let us know how it turns out. Hope this helps out a bit.

Wei
 
Discussion starter · #9 · (Edited)
wow you deserve a medal. it seemed like the white and black wires wrapped in the gray electrical tape didnt even go to the plug. so your saying splice the shielded wire from the lower harness to the white wire in the engine harness? and the black splices into what i wish you had pics after. being the first CA swap its all new to me. i had a front clip so i have it all
 
#10 ·
ch1873857 said:
wow you deserve a medal. it seemed like the white and black wires wrapped in the gray electrical tape didnt even go to the plug. so your saying splice the shielded wire from the lower harness to the white wire in the engine harness? and the black splices into what i wish you had pics after. being the first CA swap its all new to me. i had a front clip so i have it all
Click to expand...
lol thanks. just trying to help out when I can. But heres a better pic. I stripped down the shielded wire a little better for you to see. the shield portion of the wire can be twisted off the inner insulation like shown in the pic. you can get shielded wire from home depot or just take some off your KA harness. When you extend your o2 sensor and maf plug your gonna need some more shielded wire as well.

oh and please excuse my shitty ass microsoft paint skills or lack of. :)
Image
 
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ch1873857
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