Completely stumped w/ this spark issue

[new2mitsu]

Ok, i'm completely stumpped with this no spark problem. i have no spark on the 6/3 coil... i have replaced the plugs, wires, Coil, PTU, and ECU, as well as tested all wires for continuity, and NOTHING. i don't know what else to look at. i was told it'd DEFINATELY be the ECU after replacing everything else, so i order a new ECU From Jason, and still the EXACT same problem. So they tell me i got the WRONG ECU, and said my car was Cali Spec... huh? so W/E i but into it, and send mine off for rebuild, and, oh wow... no result whatsoever. So, i Paid for an ECU i didn't need, and now I'm gonna be stuck Payin for an ECU rebuild, that was totally unnessacery on top of that. Anyone else got ne ideas, cuz im already backed up almost a grand with this bull shit, and I'll be damned if this car don't run again... SOON. Pls Help... Thanks

[jason_bet]

WOW.... WOW... Thats all I can say man that sucks so bad I am sorry bro... turn around and sell the ecu i sold you.. what is the part number? cause I am almost positive that is not a cali spec.. and That wouldn't cause you to have a miss fire..

[Stealthee]

Whoever told you a Cali spec ECU would cause no spark is not smart.

Check ALL the wires going to the coil pack.

[Twizted_3KGT]

Well you threw all the parts at it that you could, sounds like it's in the wiring somewhere. Backwards mechanics ftl. Time to break out the Power Probe III! Or a DVOM if you're into the old fashion way.

Stealthee - your sig has just been a red x to me for a while now on this site.

[Stealthee]

yeah my host died a long time ago. Thats why I changed up the pic. And here the largest photo you can use in a sig is small as hell. Its almost pointless.

[new2mitsu]

yeah, jason, i planned on it... not your fault, thank you, BTW. i don't think my car is Cali spec, but maybe im wrong. What all is different about cali spec cars? i know its all emissions, but what all does that entail?
Also, do we have any kinda Traction Control Unit in our cars?

[91STT]

Here's the extract of the ignition system from the manual. It should help with your troubleshooting.

Ignition System Electrical Section

[Stealthee]

there is no traction control but the ATXs have a TCU.. transmission control unit

[new2mitsu]

so, then, basically it has to be in wiring somewhere? is there anything else that could stop spark on a single coil?

[Twizted_3KGT]

Not if you've already replaced all those parts with known working parts.

From looking at the diagram, the only thing that might single out the 3/6 coil is the wire that goes from that coil to the PTU, or the one from the PTU to the ECU. Should be a 3-wire connector at the PTU, the wire you want to check for continuity when running (or cranking) is the one with the yellow stripe (wire color code is L-Y, I want to say L = green, so it would be a green wire with a yellow stripe). The other connector from the PTU you should check is a 6 wire one, and that wire is a BR-R (brown with red stripe).

You'll want to make sure there is voltage running through each of these when cranking the engine or when the car is running.

Is there any type of security system in the car besides the stock one? A lot of times aftermarket systems will feature a spark kill, which if it malfunctions will leave you with a hard to find problem.

edit: I just read further down in that link for the manual and it basically tells you what I just did about the connectors and which to check for 3/6. But it shows how to test to make sure the PTU is good, which I assume it is if you replaced it.

[new2mitsu]

yeah, I'm not getting a signal out of the ECU, i tested that wire, and have even tried bypassing it alltogether, with another wire. i'm almost positive theres no signal coming from the ECU at all on the 3/6 coil @ the ECU. anything else that can make the ECU not send a signal, since i have a freshly built ECU and the ECU itself isn't the problem?

[91STT]

Originally Posted by new2mitsu

yeah, I'm not getting a signal out of the ECU, i tested that wire, and have even tried bypassing it alltogether, with another wire. i'm almost positive theres no signal coming from the ECU at all on the 3/6 coil @ the ECU. anything else that can make the ECU not send a signal, since i have a freshly built ECU and the ECU itself isn't the problem?

Where are you testing for signal? Right at the ECU connector or the ECU side of the PTU connector? Check that the pins in the connectors are making good contact also while you are at it. How did you bypass the wire to test? You can also check for short to ground on the brown/red (ECU to PTU for 3/6) wire.

[kmfna]

Hey new2,

If you have already followed Twizted's suggestion and know definitively that the issue is between the ECU and the PTU, and are sure it isn't a split wire, then the only possibility that I can see is perhaps it is the #11 slot on the C-52 connector or the #1 slot on the B-21 connector (taking the connector numbers from the schematics). There may be an issue inside of one of the connectors...perhaps the internal wiring is disconnected or broken. Perhaps only as a last resort, you might consider reversing the wiring connection on the B-21 (it would cause your fire time for 1/4 & 3/6 to switch) and see where the fault occurs. If 1/4 failed, the issue is with your C-52; and if 3/6 failed, the issue is with your B-21. Again, I would only try this as a last ditch effort, though it may cause other unexpected consequences that may throw off your test.

Good luck bro,
Kevin

Originally Posted by new2mitsu

yeah, I'm not getting a signal out of the ECU, i tested that wire, and have even tried bypassing it alltogether, with another wire. i'm almost positive theres no signal coming from the ECU at all on the 3/6 coil @ the ECU. anything else that can make the ECU not send a signal, since i have a freshly built ECU and the ECU itself isn't the problem?

[Twizted_3KGT]

Do you get a signal out of the other two wires between the PTU and the ECU? It is possible you got a bad ECU rebuild.

I'm not sure what signal the ECU needs to send a signal to the PTU, I would imagine its from the camshaft position sensor, but again i'm not sure. Would need the service manual to find out, but the problem could be because the ECU isn't getting the signal it needs for cylinders 3/6. Not positive how it works though.

Originally Posted by kmfna

Hey new2,

If you have already followed Twizted's suggestion and know definitively that the issue is between the ECU and the PTU, and are sure it isn't a split wire, then the only possibility that I can see is perhaps it is the #11 slot on the C-52 connector or the #1 slot on the B-21 connector (taking the connector numbers from the schematics). There may be an issue inside of one of the connectors...perhaps the internal wiring is disconnected or broken. Perhaps only as a last resort, you might consider reversing the wiring connection on the B-21 (it would cause your fire time for 1/4 & 3/6 to switch) and see where the fault occurs. If 1/4 failed, the issue is with your C-52; and if 3/6 failed, the issue is with your B-21. Again, I would only try this as a last ditch effort, though it may cause other unexpected consequences that may throw off your test.

Good luck bro,
Kevin

You're talking about risking blowing up the engine, spark at the wrong time will break rods, piston pins, etc. Not a good idea.

[kmfna]

Originally Posted by Twizted_3KGT

You're talking about risking blowing up the engine, spark at the wrong time will break rods, piston pins, etc. Not a good idea.

Agreed, that is why I didn't recommend it as a good alternative....it was definitely a last ditch, nothing left to lose, idea.