supra mk3 starting problems

[ecutec]

hi
im currently installing vems on '89 mk3 supra

i started the car but it ran really roughly and sometimes seemed like the ignition is too early as intake valves is still open and i could hear the ignition from the intak efilter...

I use a custom 36-1 trigger wheel and 1.0.73 firmware
I have the TDC set with timing light!

for doublechecking does any one have the coilpack plug picture showing which side is + and -
that is the only thing i could think of generating problems but not sure...
my setup right now...

The rpm reads nicely and i get no trigger errors(trigger swapped around does not read rpm)
when i looked at last 3 sparkplugs then it seemed like nr 2 coil was firing randomly...any way to confirm that?
should do trigger log maybe just in case?

grounds are all connected to head so no problems there
thank You!

[rob@vems.co.uk]

Is that a wasted spark coil?  If so the + will be common on all the coils and the - will be on individual pins.

Use your timing light to strobe the crank wheel - I always put a blob of paint on the front of the pulley so that I can see the rough position of the timing mark in its 3 possible locations.

[ecutec]

its 3 individual coils
i have done the timing light thing and that is correct!
here are the config files and one datalog
http://www.ecutec.ee/config.zip

hope that helps

coil plugs are connected 1,6 2,5 3,4
firing order is 1,5,3,6,2,4?

you put timing marks on each fire time so in my case teeth 1, 12, 24 ? that sounds a good idea

[ecutec]

updated config but same url http://www.ecutec.ee/config.zip

I also added trigger raw log..can someone help to interpet that?

I chekced with timing light again and founf bug
coil nr 3 (cyls 3 and 4) fires about 2 times per cycle and that what makes the engine hesitate and rpm go up and down...

the only thing i can figure is bad trigger wheel? but no trigger errors...
bad vems maybe?

[rob@vems.co.uk]

I've just run your config up on the test bench - it all looks okay, no double flashes from the LEDs there.
First test I'd try is to move the coils and their firing order in VEMS around to see if the double flash follows the coils.
Second I'd use the trigger signal generator in the tools directory to create a 36-1 signal that you can 'play' the VEMS through your sound card.
Thirdly - wasted spark can confuse some of the more 'intelligent' timing lights, its worth bearing that in mind.

Rob

[ecutec]

in this config i moved coil connected to pin 34 to 24 and 35 to 36 for testing and i must doublecheck again but double flash seemed to go from cilinders 2,5 to 3,4
I also tested my vems which is brand new and car ran the same way

also one thing i noticed now with supras vems is that sometimes it gives afterspark while engine is not cranking anymore but fuelpump still on for 1.x seconds ..weird
here is a pic of the custom trigger wheel
http://www.ecutec.ee/hammas.pdf

[rob@vems.co.uk]

in this config i moved coil connected to pin 34 to 24 and 35 to 36 for testing and i must doublecheck again but double flash seemed to go from cilinders 2,5 to 3,4
I also tested my vems which is brand new and car ran the same way

also one thing i noticed now with supras vems is that sometimes it gives afterspark while engine is not cranking anymore but fuelpump still on for 1.x seconds ..weird
here is a pic of the custom trigger wheel

what happens if you swap the coil that fires 2+5 with the coil that fires 1+6 and change the ignition outs to suit
- I find it odd that one coil works fine and the others do not.

If it gives an afterspark then you have something triggering the crank sensor only a scope will show you what the ECU is actually seeing.  When the pump is running there is the possability that the ground voltage will rise which may be injecting noise into the VR circuitry.

That trigger has huge teeth which can also cause a problem with coil hysteresis causing miss-triggers.

[ecutec]

should i machine the teeth so they would be half in size? but first i will try to swap the coils and see if double spark follows the coil

[rob@vems.co.uk]

Try the coil move first.  Without a scope you'll probably find getting the idea behind the teeth is impossible, most people make teeth too large, getting it right can be a problem.

[ecutec]

i tried the coil swap and it was always specific coil doing double spark but im not sure why but i think it is a triggering thing
is there someone here that could convert the trigger log?
i did look with old scope but that shows in real time so i only could check for bad wiring for noise but that seemed ok....did not see the number of slopes to check the correct timing. maybe the log shows different amount of events or sth

[rob@vems.co.uk]

When you say it was a specific coil doing the double spark do you mean that the coil sparked twice when moved from 1+6 to 2+5 and 3+4?
Or is it the one coil driver that is sparking twice?

[ecutec]

it was always the same coil
whatever output i connected to it...
spark is also pretty small over all coils..maybe they are old and tired?

[rob@vems.co.uk]

well that suggests that the coil is grounding via another coil...
I've seen things like this when coil packs are wired incorrectly, as one coil earths through another and they both spark as weak as hell.

[ecutec]

in that case i could try and unplug other coils and only test the single one?
bosch 3x2 coilpack was ordered so we can throw the old ones away now anyway and see what happens
IF this does not change anything then only things are trigger or wheel itself
i should post the trigger log on wiki so someone can interpet that?

[rob@vems.co.uk]

Good luck with anyone taking notice on the wiki, I'd offer to look at it but I can't honestly say it means much to me.  I use a 'scope then logical progression to solve my problem.

If the coil sparks twice regardless of the channel and cylinders its connected to then, to me, it looks like the coil is a problem.  Can you wire the coils so that you know each one is getting its own individual 12v feed and then each wire to the coil drivers in the VEMS?

The Bosch coils are good, but I'd head down the scrap yard first to see what else I could find, then I'd buy new ones of what I'd proved to have worked.  I love the Mitsubishi coil packs, the Ford ones are good and there are loads of other odds and ends you can try.  Its all down to if you're in a rush to get things working, or keen to learn how the components in a system fit together.

Rob