leolo007

whats up, just got some questions, Ive had the engine for about 3 years but Im sure some wires arent hooked up right yet.
thing is its a 92 hatch and no extra wiring was ever done. just plug and play.
so if my research is good I have two wires that need to be hooked up.
knock sensor wire and whatever the wire for the butterfly valves in the intake manifold is called.
so for the quick questions...

1) where can I find these wires in the engine bay?
2) where do they connect to the ecu? Ive been looking for a diagram of a
p72 online but cant find shit...


another thing, I had a speed shop look and my install and they didnt like it, they said the wiring was a mess because it was all crisscrossed behind the engine. I was told because the engine is jdm the ecu is in the other side of the car so wires are crossed. makes sense to me, but they said that was all crap. I think they dont know what jdm is...

S dot Camp

http://tech.hybridgarage.com/tech/5gtech/index.html

B16ASilverHonda

its real easy to do man. A couple wires at the shock towers and one wire at the ECU. that webpage should show you how to do it. Just remember the color is first tracer color after. So red/blu would be red wire, blue tracer

leolo007

thanks!! Ive been to that page and hadnt found anything before... about the wires on the shock towers arent there anymore since ecu is on different side for jdm cars, and my wires are all crossed behind the engine. Not so pretty, but much easier than extending all those wires one by one...

miahmouse

A17 is the trigger wire at the ecu. The wiring of this also varies based on year of ecu and year of motor. Difference is in what the ecu gives the IAB solenoid. essentially you just run one of the wires to the ecu at A17, and one of the wires to a power source that turns on and off with the car. From obd1 cars I've seen it's the ecu either giving or removing ground and with obd2 cars it's giving or removing a positive voltage.

example: obd2 car and engine, obd1 ecu. ecu gives ground and removes ground therefore other wire needs power->under dash works fine.

hope this helps....

Fabrik8

yes, make sure you have an ECU that is compatible with your generation engine..
OBD2 and smallframe JDM OB1 are the same, and are different than USDM OBD1...

Like maihmouse said, OBD1 completes ground, and OBD2 and smallframe JDM OBD1 sources 12V. Why Honda didn't make it all the same I don't know.

leolo007

interesting stuff, well from my engine, I found out where the iab was and there is a pink wire coming out of it and a black one, so Im guessing that must be the ground so the pink must be the trigger 12volt wire huh? So how can I be for sure. can I just guess becuase its black its ground, well atleast I already have the knock sensor wired up.

the only thing is I kinda hardwired the wire to the ecu, I dont know how good of a connection it is but I didnt have the proper tools so its good for now.

thanks for the info!!

I will let you guys know about how its all going as things progress.

Fabrik8

Well, it will either work or it won't, I don't think that you'll damage the ECU by switching the wires, but I'd really check into this before hooking stuff up and blindly testing it.. Hondata has a B18C schematic on their site, I'm not sure if it has colors or not on it..