New coil + Ign module

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Robski
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Re: New coil + Ign module

Post by Robski »

I don't have that probe in my software ??

Liteace
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Re: New coil + Ign module

Post by Liteace »

Ive just checked it on lappy and if I select:

Automotive > ignition > distributor > pri volt vs current

Just found look up table, never been in there !
DONT SHOOT YOURSELF IN THE FOOT

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Robski
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Re: New coil + Ign module

Post by Robski »

found it !

I don't use the presets.........

Liteace
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Re: New coil + Ign module

Post by Liteace »

So its all ok then and meant to be there,When I get a problem like this I always think it me doing something wrong and then you guys put the craps up me and tell me its looks ok or Ive got the wrong probe selected.

Its holiday here today, I was just about to jump in van and drive to the workshop to re-test it, I can relax now

:lol: :lol:
DONT SHOOT YOURSELF IN THE FOOT

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Robski
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Re: New coil + Ign module

Post by Robski »

That's why i asked you if you had created the probe & look up, had it been wrong could have given inaccurate results.However the look up table looked ok to me anyway, but i had i have wanted a -1 - +9A scale i would have duplicated & edited the low amps 20A probe . If you ever do create a probe make sure it is 100% correct :wink:

I noticed it looks a current limiting system too, is that correct ?

A word of advice if you choose to take it, don't rely on the presets, set your own channels/probes/scales/sample/time etc :)

Liteace
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Re: New coil + Ign module

Post by Liteace »

Most of the time I do set me own channels/probes/scales/sample/time etc, this time I didnt, I dont know why. The module is a GM hei unit with built in current limiter
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Autonerdz
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Re: New coil + Ign module

Post by Autonerdz »

Liteace,

That's very interesting.....

I suggest you look carefully for any components that may be tied into the coil negative. Examples would be a tach, alarm system, fuel pump relay, remote start, etc. Anything tied into the coil negative could create what you are seeing there.
Tom Roberts
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Autonerdz

Liteace
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Re: New coil + Ign module

Post by Liteace »

There's nothing in the system at all, its direct from coil neg to ignition module
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Fat Freddy
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Re: New coil + Ign module

Post by Fat Freddy »

The module is a GM hei unit with built in current limiter
Is this a DFI with EST and bypass control?

What was the original fault?

Have you looked at the IC from the PCM.


And for interest. Here's a similar capture from a Mazda, new coil and module also. As far as I got was it appeared to be caused by the command from the PCM (the main fault disappeared after a couple of days, and six months later. Still no problem.) but it did some really weird things. (this was a good day).

Image
Image

Avdr
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Re: New coil + Ign module

Post by Avdr »

I'm sorry, I can't offer any advice, but I do have questions, could somebody more learned than me shed some light on these points?

What are we actually seeing here,
ie. How is it possible for the coil current to still be 6A after the PCM has removed ground path. I assume this from what is being shown in CHA, after the 1.2ms time to saturate the line rises to 12v again?

I'm not at all familiar with the setup, and have never delved much into the reams of coils with more than a simple power and ground circuit. I'm aware some can be triggered on a 3rd wire, and even have a forth wire for a feedback of succesful spark (thinking about COP here). I realise a DIS on wasted spark would have a common power lead, and 2 switched negatives.

So, coming back to this case, if on CHA the ground return has been removed, why does it not induce a spark? We see that the ground path is completed to charge the coil, then it appears that the PCM drops the path, surely that should induce a flux collapse there and then?

Bit confused,

Thanks

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