Engine Harness Power

[Birdmanslopy]

My buddy has a crx and he is doing the 4g63t swap and he wanted me to ask a question.
He has asked this on honda-tech but was critisized for it so he wants me to try here.

i got a wire harness off a 92 1G eclipse. ive got everything for the sensors an was wonderin if i could take a power wire from the ignition an run it striaght to the harness to power the ecu? if im thinkin wrong how should i do it

 

[lVlossyOak]

bump

 

[compression]

ha..ha...ha... stephen and jay? who woulda thought? im not a dsmwiseman or anything but it sounds to me like thats feasable

 

[1gjosh]

i believe compression is right on this one, although ive never seen anybody put a 4g63t into a crx , i would say yes just go ahead and tap into your ignition switch just make sure you get a good connection you dont want to lose connection to your ecu from hitting the wire or something.

 

[steve]

If your going to be running a matching ECU too just graft in the harness the same way it was used. It's three circuits. Constant backup power, constant power to the MPI relay, and the Ignition run circuit. Anybody considering the swap should be able to read the wiring diagrams from both cars and figure it out in one or two beers.

Steve

 

[cornflake]

do you have a build thread anywhere? post link or ban!

 

[lVlossyOak]

almost everyone from my town is in this post ha ha ha ha thanks for tellin me about the constant power i knew i shoulda got that other relay. im pretty familuar with the honda wiring, i cant get ahold of a real service manual at the moment (not ## autozone manual) soon as i do ill knock it out no problem.

 

[steve]

The guys at manualcd.com were kind enough to provide samples that could help you.
http://www.ecanfix.com/users/manualcd/gift/dsm/1g_circuit_diagram.pdf

Steve

 

[lVlossyOak]

From looking at the circuit I think my idea will work because all the power wires end up coming together at one point. Just the "constant" power wire? I don’t see where to hook one up. I’m not to fond of ALLDATA's info but whatever they’re using has more info. I’ll take another look just to make sure I’m not missing anything. If any of you guys find something I might need to know I’m open to suggestions.

 

[lVlossyOak]

Well you were right steve, yesterday i finished the engine harness looks pretty good now . but one thing happened i cant find were the O2 wire (grey/white) goes . ive checked the diagrams but no luck maybe im thinkin of a diffrent plug. it shows a 4 wire O2, if im not mistaken it was a 1 wire. anyone got any imput on what pin an plug it goes in.
P.S. if i have grammer errors sorry bout that the spell check dont work.

 

[steve]

We use a 4 wire sensor. The sensor output runs to pin 4 on the ECU. The other wires are signal ground, heater power and heater ground. The normal DSM O2 sensor connector is a round 4 pin below the water filler neck. There is a metal clip to hold it to the block.

Steve

 

[lVlossyOak]

Would it happen to be 2 black's, red, an white? what size fuse should i put on the constant power?

 

[steve]

Yes, on the turbo cars the power (red pin 3) for the heater is run from the output of the MPI relay. We don't feed the O2 sensor constant power it would burn the heater up and run the battery down. The MPI fuse is a 20A link. part of the 3 or 4 that attach directly to the battery positive on a 1G DSM. This stuff is in that pdf I linked you to.

Steve

 

[lVlossyOak]

i must have missed it sorry but its all fixed now thanks for the help. cant wait to hear it run