hey guys,

Iam now on week 5 trying to figure out the same problem ive had with a wiring issue. . . i once again, fried my #1 coil pack today. i have no idea what else to do. . ive check the harness for any wires grounding out. .none. ecu and j30 ignitor chip is good. . when the car does run, it runs on 5 cylanders on and off every other second. . ive asked before, and i have to ask again cause im desprate to have this thing running. . ive also tried to find diagrams on the harness, and its either not wut im looking for or to small to understand. . all i can think of is the 2 black wires on the 3 pin plug to the ignition harness is wrong? both are grounds correct? looking at a buddies harness, one of the black wires connects to his #1 signal wire on the harness. i did that and it fried my coil pack. . can anyone tell me if im over looking somthing or doing something wrong please. . im completely out of ideas.....thank you

i want to say i have no "IGNITION SIGNAL"???? were in the world is that wire! im sure from the ecu its pin 10 and 20. these two wires join together in to 1 wire and go to the '3pin' ingnition plug i beleive. . then from the plug to the #1 ignition signal wire?? THIS is what im trying so hard to figure out...and if this is correct, then i must be doing sumthing wrong because its causing the coil pack to fry...

If you keep blowing the #1 coil pack I would run 3 new wires to it.

Run a new signal wire between the ignitor and coil pack, and a new ground from the other small wire that's left over, and the middle/larger wire is the 12+ feed that comes from the 3 pin connector near the ignitor. I have a completely separate sub-harness for the #1 coil pack since the signal and 12+ wires were touching.

You don't need a wiring diagram to figure that out, just take all the plastic and tape off your coil pack harness and you'll see which wire runs where, and then how to by pass the OEM wires and add your own.

~Alex

well thanx for replying. ive had a hard time just getting that.. . but thats the thing man. i 'have replaced the wire' already.. i think my issue is either one of the 2 wires on the 3pin plug to the ignition harness.. i looked at a buddies ignition harness and compared to mine. . each coil pack obviously has a ground signal and power wire,yes... but # 1 signal wire connects to ONE of those black wires on the 3pin plug also right???(i dnt have that at the moment) i have tried both wires, and it just grounds out #1 coilpack. wich is what i believe makes the car run only 5 cylanders every split second i rev or drive it and will eventually fry . .

all i know is that i have seen this motor run fine before i bought it. and when i swapped it in to my s13, all the sudden #1 wasnt sparking at all. . i cut the existing wire, and ran a temporary new wire from the ignitor strait to the pack. it fired., but ran like doo doo. .

i need someone to verify were those 2 black wires go FOR SURE.. i know one is a earth and one is apparently the ignition signal/timing loop?,and pins out to the ecu.(10, 20) . . and the other is a chasis ground.

needless to say, if im looking at this raw harness what do i do? or more specificly, were do the 2 black wires go.??? i swear im not super dumb, but guys, im serious when i say ive tryed everything. . im starting to think im over looking the problem. . can some verify for me plez. im about to go pull my entire harness out. thanx again!

is it also TRUE if you o2 sensor goes bad,, it will mess with or screw up the spark for #1 coil pack. . i thought that was pretty bizzare when i was told that...

You need to go through the wiring harness with a diagram and verify everything is connected to the ECU pin it is supposed to be and NOT grounded out when it's NOT supposed to be. Here's coilpack wiring 101:

1) There is a common "ON" power wire daisy-chained to each coilpack plug, it is the thick white wire on each coil plug.
2) There is a common ground wire daisy-chained from each plug and grounds at the loop which is held down by the #6 rear coil pack bolt. There should never be voltage on this line.
3) There is a black with colored-stripe wire to each coil from the ignitor and then back to the ECU. The ECU grounds each wire individually to discharge each coil in time. These wires need to be checked for continuity back to the corresponding pins on the ECU plug. Also, the #1 cylinder signal wire (B/R) is the only signal wire that is also connected to ground. Don't ask me why, but that's the way it is.

If you can verify this is all correct and you are confident in it, then I'd start looking at the #1 coil driver in the ECU. It could be fried.

And whoever told you that a bad O2 sensor can selectively fry your #1 coilpack is a dumba$$. Unfriend them from facebook.

lol'd at the o2 sensor thing....well i greatly appreciate it man.. i think i mentioned that i had a J30 converted ignitor, so the ground is a tad different... im deffinatly aware of the ground that daisy chains, as well as the white power wire. . what you stated on 3) in your paragraph was exactly what i needed verified. which brings me to a stop again. . the 2 wires on the 3pin plug are both grounds. 1 is just a chasis ground loop, and the other tree's throughout the whole engine harness and meets back to the ECU... with that being said, the one that goes to the ECU is supposed to meet to the #1 signal wire, but . . . it doesnt fix my problem. it "GROUNDS" the coil pack out and ends up frying.. WTF... i guess ill relook it all..... but do you have to do sumthing special,,,like set the motor to TDC mabee? anything? since its a timing thing? IDK im probly dumb for that. mabee grounds have to be hooked at an exact point in the ignition harness. . The problem im having is deffinately a stupid one. One that would seem easy to fix with a ground tree. haha. but i cant find the problem to save my life... thanx again. im goin to POST a picture and show you my situation exactly.

I'm almost positive that it has something to do with that ground. I think you are on the right track in that one of the grounding wires is constantly grounding the coilpack which ends up continuously passing power through it and discharging it almost like it has zero dwell time. If you can take a picture of the J30 ignitor wiring, that would be helpful.

Is there any way for you to convert back to an RB25 ignitor?

yeah thats what i was thinking.. i will definately post some pictures of the wiring today, i also have the engine harness out and stripped so i can show you how the wire is ran. . i was looking over it all last night and couldnt find anything out of the norm. maybee something will stick out too you...

Hi did you ever resolve this issue I'm having exact same issue frying #1 coil pack due to its signal wire always earthing out I've cut the wire going back to the 3 pin wtf plug sparking now without coil heating up but wont run properly done everything from swapping coils out I've tryed another ignitor and another ecu still no fix. any advise appreciated

I had this problem doing a Rb25de swap into my S14 silvia. I was also using a rb20det ignitor pack and coil loom. BUT I was using the rb25 engine loom. The way to fix this issue is too add a factory rb20 resistor to the ground wire coming off of the three pinned plug that plugs into the coil loom. The 25 loom does not have this resistor.