rb25 ignition harness help pwease

[thrasher324]

i have a 89 s13 with neo rb25. after replacing the HG ive been having hard time trying to get the car to just run right. it starts except it boggs like crazy and i eventually realized that its misfiring. so basically this one time i cranked too long causing the ignition harness to burn a little bit. so i cut the wires to extend them but i dont know where this one white wire goes to.

it looks like this currently
http://i35.tinypic.com/244rwox.jpg

the #4 is the mysterious wire. i know this isnt a hard thing to do but wiring is my worst nightmare as everyone else. i looked literally everywhere for the wiring diagram that actually tells me colors but i couldnt find any.

And i also checked to see which pin from the connector to the coilpack has power. and it all came down to a random result.

cyl #1
Blue gets power
black
black/red

cyl #2
white gets power
black gets power
red/white

cyl #3
white gets power
black gets power
pink

cyl #4
white
black gets power
pink

cyl #5
white
black gets power
pink/white

cyl #6 white
black gets power
pink/green


if you could give me some info on the wires i would very much appreciate it.

thank you
ed

[Darius]

Have you pulled your entire coil harness apart?

The white wires are supposed to see 12V switched ON power. The black wires in the middle are the grounds for each coil and should never see 12V. They are all daisy-chained together so they should all read the same (0V). On cyl #1 where the black does not have power and all the other coils do already tells me that there's a break somewhere between the grounding wires and cyls #2-6 are shorting to 12V power.

My assessment is that there are shorts in the coil harness. My harness shorted out while sitting in the sun at a car show for 5 hours. When I went to start it, it wouldn't pop ANY of the cylinders off. As soon as I took the electrical tape off, it was all melted and goopy. I separated the wires and it fired up like nothing ever happened. B*itch!

[thrasher324]

Have you pulled your entire coil harness apart?

The white wires are supposed to see 12V switched ON power. The black wires in the middle are the grounds for each coil and should never see 12V. They are all daisy-chained together so they should all read the same (0V). On cyl #1 where the black does not have power and all the other coils do already tells me that there's a break somewhere between the grounding wires and cyls #2-6 are shorting to 12V power.

My assessment is that there are shorts in the coil harness. My harness shorted out while sitting in the sun at a car show for 5 hours. When I went to start it, it wouldn't pop ANY of the cylinders off. As soon as I took the electrical tape off, it was all melted and goopy. I separated the wires and it fired up like nothing ever happened. B*itch!


thank you for some good info. and yeah thats what im thinking also but i just cant find any info on the neo wiring diagram that has colors. or is there any other way to wire it up right by using those multimeter things?

[Darius]

The NEO is relatively rare compared to the S1/S2 so finding a wiring diagram with the exact NEO coloring will be difficult. The wiring is the same, you just have different colors. In fact, if you exchange red for pink in your wiring colors, it almost exactly matches up the standard RB25 diagram.

In general the plugs go as follows:

White: 12V switched ON power
Black: 0V grounded to loop at rear of valve covers
Signal wire (varies in color): 0V except coil #1 when switched power is ON (if I remember correctly).

[thrasher324]

The NEO is relatively rare compared to the S1/S2 so finding a wiring diagram with the exact NEO coloring will be difficult. The wiring is the same, you just have different colors. In fact, if you exchange red for pink in your wiring colors, it almost exactly matches up the standard RB25 diagram.

In general the plugs go as follows:

White: 12V switched ON power
Black: 0V grounded to loop at rear of valve covers
Signal wire (varies in color): 0V except coil #1 when switched power is ON (if I remember correctly).

should i just use this and change the pink to red like you said?
http://rbforums.org/pics/rb25diagram.jpg

i also have the neo pinout which is completely different than the wiring diragram above so should i look at that too?

[Darius]

Yes that is what I was comparing against anyways. The wire colors are very similar.

You can look at the NEO pinout too, but it won't tell you much unless you are checking the continuity of the wiring from the ECU to the coil harness to make sure it is good.

[thrasher324]

Yes that is what I was comparing against anyways. The wire colors are very similar.

You can look at the NEO pinout too, but it won't tell you much unless you are checking the continuity of the wiring from the ECU to the coil harness to make sure it is good.

okay when im free from school im gonna check it out and get back to you lol