Hey guys i posted earlier with a similar topic, what I said was wrong and i have now figured it out.
I have a 1996 civic coupe with d16y8 swap from a 99 civic.
the motor has the 99 harness on it right now and the guy just connected it to the 1996 ECU.
The speedometer & rpm is not working but the fuel gauge and temperature gauge are working.
It's also throwing a check engine light but I don't have a reader to get the code.
The guy says that I need to get a 1996 wiring harness and connect it to the 1996 ECU.
I'm thinking I can just get a 1999 ecu and plug it in to the 1999 harness that's in there right now.
Will a 1999 ecu work on 1996 shell?
Also, if not, can i just get the 1996 wiring harness?
Will everything work right with a 1996 harness & 1996 ECU on a 1999 d16y8?
someone please help, I have someone willing to come and install the harness. i just don't know if i should order it because I don't know if it would work on a 1999 motor.
Thanks!!

 

the guy whos swaped the motor put the exact same motor back in...just a differnt year. I dont think the harness & ecu will mater. 96 -2000 civics are mostly the same. (except for si), but if im wrong feel free to correct me. Also i would call a honda dealership and talk to the garage/parts section.

 

Uh, post a picture of the plugs going into the ecu. You cannot use an obd2b harness (99-00) with a obd2a ecu (96-98)

To answer your question, yes you can get a 99 d16y8 ecu and it will work fine. The engine harness has nothing to do with the chassis.

 

****, hes right. Your are gonna have to do research on this. You should really call a honda dealership.

 

Thanks for the quick response guys.
I took some pictures, the harness looks like it hooks up perfect to the ecu.
There is a wire with a blue connecting piece that's coming off the harness that's not plugged into anything, it's the wire in the second picture i posted.
What is that wire for?
Also, if i were to get a 99 ECU, would i have to change out all of the dash & floor wiring and all of that and convert all the wiring in the car to a 99 ex? Or would the 99 engine harness work and 99 ECU work with a 96 dash & floor wiring?
Sorry for all of the questions haha, i'm new to all of this stuff.
thanks guys!

 

here's the wire that i'm talking about
http://s1134.photobucket.com/albums/...=civicdddd.jpg

 

The blue plug in your pic above is the connector that allows you to check the engine light without a code reader. If you use a paperclip and join the two pins on that plug it'll make the check engine light blink and you can read the codes.

 

Ok so everything works fine in the car except the speedo and rpm gauge. I tried that paper clip thing and it didn't work for some reason. Do you guys think I should by a 99 ecu and then ill be good? Because everything looks like it clips up perfect on the harness, there's no missing wire and everything works in the car accept the speedo and rpm gauge. I pulled the cluster out and everything is connected right. So do you think I should get a 99 ecu and eveything will work? Thanks guys