7mgte spark issues+

[twistedshadows]

hi im having a some problem with the ignition system but first the cars history the car is a 88 na auto that when i picked it up was already converted to a 5 speed the engine is a engine ive been building for a few years now its a 87 7mgte the harness is also from a 87
the problem is out of the 3 coils im only getting constant strong spark on 1 of them the other 2 i get almost no spark (1 spark per every 30-40 revolutions of the cps if that)
i have test the cps (all 3 cps i have tested good) even swapped for a known working 1 didnt help
i checked all the wiring for the cps to the ecu no shorts not cuts its all good
i tested the coils all 9 of my coils tested good (i have 3 sets)
i tested the wiring from the coils to the igniter no shorts or cuts all good
i tested the wiring from the ignitor to the ecu no shorts or cuts all good (the ignitor is off of a car that was running a week ago)
i tested the ignitor per tsrm insturctions tested good
i have 12v to all coils
i have 12v to the ignitor
i even swapped the ecu twice no diffrenece
i even did the ground mod on the ignitor no diffrenece
i have taken the coils off of the mount and plugged each 1 into a diffrenet plug all coils have strong and constant spark on the same plug and almost no spark on the other 2 plugs
i dont know what else to do ive checked all the grounds and everything i can think of my cps is good my ignitor is good and my coils are good but i only get spark on the 2-5 coil and almost no spark on 1-6 and 3-4 coil any any any help at all would be great
joe

 

[hvyman]

plug wires in wrong spot on coils? cps 180* off? timed correctly? have you pulled plugs and grounded them to see what cyl are firing?

 

[twistedshadows]

timing has been set correctly plugs on correct coils i have already said which wires are firing 2 and 5 ive been around the block when it comes to 7m's i just cant figure this out ive never seen 1 coil fire and the other 2 basically do nothing
at first i had the timing set and i cranked the motor but i couldnt figure it out so i pulled the cps and spin it by hand works just at good and saves the battery (it doesnt matter if i set everything up like i was going to start the car or spin the cps by hand i still only get spark on the 2-5 cylinder coil and no spark on the 1-6 and 3-4 cylinder coils)
sorry if i seem insulting i dont mean to be just trying to get straight to the point and cut out any confusing bs but please keep throwing ideas at me maybe 1 will stick and fix the problem
joe

 

[twistedshadows]

just a update i checked for codes and im getting 22-32-51 non of them have anything to do with the timing system so i should be getting spark but i may be wrong keep sending ideas my way
thanks
joe

 

[noa324]

4 got to mettion it was an na b4... i own the mk3... wires are old but they worked on the part car that we bought... driving us crazy working on it night and day feel free to bounce ideas off us ..........

 

[twistedshadows]

ok heres a update i now know why im not getting spark on those 2 coils im not getting the tigger signal on igda and igdb well if i remember correctly those are the 2 wires all the wiring between the ignitor and ecu is good im going to check all the grounds and positives on the ecu and see if i find anything if any 1 else has had a problem like this before and knows the cause that would be great but till then im still in the hunt to solve this problem
joe

 

[hvyman]

test your afm, your tps, and check the wiring to your water temp sensor and test it.

 

[twistedshadows]

how would those sensors cause only 1 coil to get a trigger signal and not the others?
i will test the wiring for them because i am getting a few sensor codes dont remember the codes right now but i didnt think that they would cause any ignition issues i thought the cps was the only thing that would mess it up (trigger signal wise)
joe

 

[hvyman]

your right there not on the ignition circuit. but if you look at the trouble tree for a no start both the water temp sensor and afm are on the list of things to check.

http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=FI&P=12

 

[twistedshadows]

yes but if i read the diagnostic chart correctly those would be tested after the ignition system passes good which from what i can guess (yes i said guess because i dont know and unless some 1 who does shows up thats all i can do) would mean that those systems dont have anything to do with telling which coil to fire (they will have something to do with timing but i dont see how they would make the ecu chose to fire only 1 coil) i will test all of those circuits to make sure there working but im just trying to understand why the ecu would only tell the ignitor to fire 1 coil
joe

 

[hvyman]

have you tried swaping plug wires?

 

[3p141592654]

LOL at this thread.

No trigger signal, well actually those aren't triggers those are addresses to select which coil to fire. IGt triggers the ignitor.

1) How do you know IGDA and IGDB are bad? Did you use a scope. You won't see much using a DVM.

2) Did you scope IGDA/B at the ECU terminals? If okay at the ECU then most likely a wiring problem.

3) If nothing at ECU, do you actually have a 7MGT ECU installed? The 7MG ECU doesn't use IGDA and IGDB and apparently this was an N/A originally.

4) Given that you have three unrelated codes all pointing most likely to bad wiring, I would have to surmise that your wiring would be a good place to focus.

 

[twistedshadows]

well i do not have a scope i used a logic probe (works just fine) i do not have a signal at the connection for the ignitor or the connection at the ecu i have used a multimeter set to 200 ohm scale and checked the wires they all checked out good with less then 1 ohm of resistence (.2-.5 ohms at the most) this harness is old and has some brittle wires im going to borrow another harness from a friend and see if that helps if it does then i will redo my harness pin to pin which would solve any problems i hope
joe

 

[jetjock]

LOL at this thread.

Me too. The other guy is the one who needs a logic probe

 

[twistedshadows]

what? did i do something wrong or are u laughing at the other guy? he would normally be on the right track accecpt ive done all that stuff already oh and yes its a 7mgte ecu for a manual car actually we have 3 of them and i can still grab another 1
but if any 1 has any ideas i dont really care what they are keep throwing them my way and ill keep checking (waiting on my buddy to get the other wiring harness to swap them out and see if that fixes the problem)
joe

 

[jetjock]

the other 2 i get almost no spark (1 spark per every 30-40 revolutions of the cps if that)

 

[twistedshadows]

ahhhh im confused now is that important or are u just making fun of me :aigo:
joe

 

[supra srt]

have you tried swaping and ecu from a running car. I have a similar problem and I open the ecu and found a broken/burnt contact. You can look here (car wont start, ignition 1990 turbo) to see the pic of my ECU. I havent fix my car yet since I am leaving tomorrow for a year.

 

[twistedshadows]

ive tried 3 diffrenet 7mgte m/t ecu's non of them fixed the problem i opened 2 of them up thinking they might be burnt (my friend went through 3 ecus on his 1j swapped mk3 before we redid the wiring that a shop :cough: jg autoworks miami fl :cough: screwed up) and i found nothing wrong with any of them i could be wrong tho never know
joe

 

[CHRIS EICHMAN]

you didnt by chance put new connectors on your cps? the reason i ask is that i did that and connected the red to red and blue to blue and what i thought was yellow to yellow and the three commons to black. I was pulling my hair out when i finally traced the wiring back to g1 g2 and ne and found out that the color of the wires coming out of the cps dont match up w/ the ones from the harness. I felt really stupid for not tracing them back to the ind pick ups. Any how good luck with your solution.