Civic+Wrx

Hey everyone I am new to this site, i have gotten alot of usefull info off of this site so I decided to join!
I am doing a swap for a friend he has a b20b frankenstein, anyhow he has a non vtec 99 civic hatch obd2b and the engine is an obd2a he bought a few harnesses and none work due to the one piece design verse the 2 piece (acura)
If I get him a 99-00 Si obd2b engine harness will that work on the engine? As for the ecu he has every jumper known to man so not to worried about that we are going to run an obd1 ecu he has both obd2a and obd2b - obd1 jumpers!
Please help thank you in advance!!

B serious

iTrader: (1)

Just use the 99 hatch's harness. You will need to extend a few wires and convert from 3 wire to 2 wire IAC. No biggie.

You want to match the harness to the chassis. An OBD2B civic EX or Si harness would be plug and play. They both have VTEC and knock functions. Although the EX harness requires O2 sensor wire lengthening.

You'll need to wire the 2nd O2 in via a subharness either way...if you want to have it there for emissions tests.

The motor doesn't care which harness you use. The ECU doesn't care which motor you use as long as all the sensor signals go back and forth as they should.

tony_2018

You should automatically realize that you can't use an obd2a civic harness because you'll end up with 2 A plugs going to the ecu. So that leaves you with the obd2b civic harness.

B serious

iTrader: (1)

The OBD2A plugs at the ECU don't matter since he has a sandwich harness. But the green plug to the dash harness won't work.

tony_2018

I see what you're saying, I can imagine how it'll look but thats not my taste to run things that way. I rather keep it straight and not confusing looking. But you still can't use an integra engine harness in a civic though. If OP is staying obd2 than he will need to run those wires you stated.

Civic+Wrx

His engine harness off the d16y7 engine doesn't seem to match vertually any plugs on the b series engine, your saying it should?

tony_2018

Match vertically????

Civic+Wrx

Sorry I spelled that wrong, anyhow What I meant was the factory engine harness doesn't match most of the plugs on the new engine....

B serious

iTrader: (1)

Plugs that won't match with the Y7 harness:

-IAT (intake air temp)
-Distributor
-IAC (idle air control)

Everything else matches, IIRC. You just solder on plugs that do match. You have to do a 2 wire IAC conversion.

The Si's harness may require the following mods:
-IAT
-distributor

So....not too much difference. The Si doesn't require you to lengthen the primary O2 wire, though. It also has a knock sensor plug. You won't need to lengthen the wires along the backside of the head either.

There are advantages in simplicity to using the Si harness. If you don't like wiring...use the Si harness. Its just about as plug and play as it gets.

It takes me about 20min to modify a Y7 harness. For me...that's easier than sourcing a stolen harness from craigslist and then having to drive out to some non-text replying motherfu#&er to go get it. Then again....I usually have harnesses laying around that I took off junkyard cars and JDM swaps (including ECU connectors). I have mad plugz and pins, y0. I try to lengthen wires using the factory colors.

Civic+Wrx

Thanks for the help Guys
"Bseries" thanks again man that info was very useful between those two harness I should be able to make it work, I also will try and do the wiring as apposed to trying to find an Si harness next to impossible to find anything in Alberta
"And yes the one I probably would find would be some stolen hacked up harness" haha HEADACHE......
One question what did you mean by IIRC?

shotoutacc0rd

"If
I
Remember
Correctly"

B serious

iTrader: (1)

No problem. Check out the FAQ's (Freakish Aardvark Questions) in this forum. Helpful and detailed instructions are available.