Blacktop Swap, No spark 1989 240SX

[drkidd22]

Hello all,

I have swapped a blacktop SR into my 240sx. Everything seems to be working just fine ( get fuel, ECU getting ignition signal when key turned to start, ECU triggers the relay) but the problem is at the CoilPacks. I got the (E) terminal from each coil pack going to their respective pin on the Ignitor. I get 12V on pin (2) of each coilpack when Ignition switch is turned to the On position and the problem is that when I ground pin (1) the 12V from pin (2) are coming right back and making a short to ground. I tested the CoilPacks and get 1Ohm from pin 1 to 2 like on the FSM. Anyone please? I did a little diagram, hope someone can help. I tested the Ignitor chip and is good as well.

http://www.lapenda.com/images/myschem.bmp

[slider2828]

Check your grounds on the harness itself. On the coilpack harness there is a small lead to a chassis ground. See if that is connected or maybe snapped off because it is pretty thin, but literally right after the 4th coil, there is a little lead with a ground with a circular connector on it.

[drkidd22]

Check your grounds on the harness itself. On the coilpack harness there is a small lead to a chassis ground. See if that is connected or maybe snapped off because it is pretty thin, but literally right after the 4th coil, there is a little lead with a ground with a circular connector on it.

I made double sure that the coil packs are grounded (re-grounded) to the bolt on back of the engine, took the coil hardness apart and it was clean,get 12V with ignition switch (ON) to pin #2 of all coils, all wires (E) are going to their respective coils. Are the coilpacks supposed to get warm with the ignition switch in in the on position? Checked all cables and couldn't find anything shorting out. I get good continuity on the Ignitor, (I got four ignitors from 95 Q45 which are plug and play (same part number).:-/

[drkidd22]

Ok, so i've again checked everything and still nothing, I'll just go to the yard and grab another igniter set from a Q45 and see what happens even though the ones I have pass the continuity test.:duh:

[slider2828]

I forgot if you need to rewire the ignitor, but from what I remember you don't. So how do you know you aren't getting a spark? Are you removing the coil, sticking a spark plug in it and putting it on a screwdriver tip?

[smelly240]

if ur ground wires are getting hot - theres high resistance in the ground for the harness...

[drkidd22]

I forgot if you need to rewire the ignitor, but from what I remember you don't. So how do you know you aren't getting a spark? Are you removing the coil, sticking a spark plug in it and putting it on a screwdriver tip?

I am trying with a aprk plug just like you said and with a screw driver into the coil as well, no spark from any of the four coils. My starter makes a weird noise also when trying to start the car, only makes it some times and I think Is due to a short inside the coils or something because it doesn't make the same sound with the coils unpuged

[drkidd22]

if ur ground wires are getting hot - theres high resistance in the ground for the harness...

I tested today and the 12V from the middle in the coil plugs are coming right back to the ground cable in the same plug, the way I tested was by unplugging the entire coil hardness from the main hardness and applied 12V to the "middle" cable and then with the DMM I get the same 12V coming to the ground cable. Bad COILS? Took the coil hardness apart and tested for continuity on all cables and no shorts found, did the same test but this time without a coil and the 12V where not present at the ground anymore.

[slider2828]

hmmmm... all 4 that is so unlikely, but just try 1 at a time to see if that is possible.

[GSXRJJordan]

I think you've got a wiring problem, rather than a coilpack problem... the first thing is, you can't troubleshoot this like a normal circuit, it's a little backwards: both +12V and ground should get 12V from the igniter, and the 'ground' is switched to ground when the coil is supposed to fire. A switched-ground circuit (rather than "switched-hot", or switched-12V) is common in stuff like this. First off, make sure your igniter is wired correctly - look at connector 14 in my pin-to-pin I made (for a redtop, hopefully the same colors):

http://img251.imageshack.us/my.php?image=hpim0254dq0.jpg
(save to your computer and zoom)

My guess is you've got something screwy going on between the ECU and the coils, rather than all 4 coilpacks being bad.

Oh, and if anyone knows any of this is inaccurate, please PM me.

[drkidd22]

I took my wiring hardess apart and couldn't find anything, wrong at all with the wiring, all colors match, tested for continuity and all that shit, now It's still doing the same thing, even with the ECU unpluged the coilpacks get hot, burning hot as well as the battery terminal with the coil hardness unpluged nothing of this happens or if I have the coil packs oput.

[drkidd22]

both +12V and ground should get 12V from the igniter, and the 'ground' is switched to ground when the coil is supposed to fire.


I was looking at the FSM diagram and dont see any place in the diagram that shows the igniter send the 12V to pin2 of the hardness, the 12v to the coil hardness (pin2 on all plugs) comes from the Ignition switch when the key is turned to the on position and the ECCS relay is triggered by the ECU. It's basically a chain reaction on the relalays. If there is any oder way than the FSM to rewire this let my know and I will try.

[bik]

Be sure you have the correct ECU conected hahaha

friends dont let friends coenct ECUs Y_Y

that drive me crazy for a week

[Canaduh]

Be sure you have the correct ECU conected hahaha

friends dont let friends coenct ECUs Y_Y

that drive me crazy for a week

Sad to admit but that happened to me as well. Took like 4 days to figure out what the hell i did wrong.

[drkidd22]

Be sure you have the correct ECU conected hahaha

friends dont let friends coenct ECUs Y_Y

that drive me crazy for a week

Yeah I do, it's an E5, I saw the thread, but that makes me think of something dough, that guy at least was getting spark from #1:ugh:, so I might try my 240 ECU

[drkidd22]

So all the wiring from the CoilHardes 12V on Pin2 on all four plugs and gound on Pin1 get hot, including the coils. Also the ignition wires on the ignition switch get real hot, almost burned my hands (this all happens with ignition switch in on position and coil packs in ONLY). This as I been saying only happens when I plug a coil pack in the coil hardness, none of the wires mentioned avobe get hot when a coil is not plugged in but just the bare coil hardess. This is a new install by the way.