Running issues, now dead

Breakzero

Breakzero

Active Forum User
Hi,
Hope you guys can help. In short I have an L28 which is running twin SUs.
Car ran fine for years, then started to run terribly.
To the point was firing up on less cylinders at times when starting up. Thought it might be the carbs, as I haven't gone over them and set nice for a year or so.
But after retrying to get them right for a few nights now, they having none of it. Backfiring out carbs at first and now exhaust also. I Cant seem to get them happy at all. All sorts is misbehaving.
So I went back to basics plugs, compression. Timing etc.
Then finally moved to ignition and Pulled coil lead off and back on, and Now have no spark at all. Simple as that. Which leads me to think that, all the running issues and difficulty to get the car running right was either coil starting to fail or dizzy.
What do you think?
 
Breakzero

Breakzero

Active Forum User
The cap and Rotor are unknown age, however cap looks to be in good order. My Dizzy is the Reluctor Spinning 6 point star type (Not point / breaker type?).
I have had the Coil off today (3 ohm model accel super stack yellow) and there seems no OHM resistance across Primary circuit? Positive + to - negative?
There is OHMs from Centre to either side of 9,500.

Also can anyone advise what is this below the coil, is this a type of Ballast?
 

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Breakzero

Breakzero

Active Forum User
Rob Gaskin said:
Check the wire that you pulled off the coil. It may be broken.
Click to expand...
It was the Main coil wire to the Dizzy. pulled it off and back on then the car had no spark.
Any way to test this? I Don't seem to get any Continuity down this, nor any of my HT leads... is that normal or not?
 
jonbills

jonbills

Membership Secretary
Site Administrator
By no ohms, do you mean zero or infinite? It should be 3 ohms of course.
 
Rob Gaskin

Rob Gaskin

Treasurer
Staff member
Site Administrator
Suggest you draw a diagram of your coil and 'ballast' connections and post it on here. Never seen that ballast before.

However if it was running, then misfired and then stopped after you removed the ht lead I suspect the connections are in the correct places. IMO you either have a faulty 'king' lead of a faulty coil. Are all the connections clean and terminations good?
 
Breakzero

Breakzero

Active Forum User
Rob Gaskin said:
Suggest you draw a diagram of your coil and 'ballast' connections and post it on here. Never seen that ballast before.

However if it was running, then misfired and then stopped after you removed the ht lead I suspect the connections are in the correct places. IMO you either have a faulty 'king' lead of a faulty coil. Are all the connections clean and terminations good?
Click to expand...
Thanks Rob,

Yes all connections are clean and good, I rewired the car from scratch a few years ago with an EZ wiring loom kit. so wiring is all clean tidy and correct spec. Yes was running OK for years, then seemed to go off and progressively get worse. then now just started to tackle it, and this happens as I start to go over the different components.

Do you know what is the correct Coil for this spec car? reluctor type Dizzy and L28 on Carbs? should it be 1.5 OHM or 3 OHM? and Should I run a Ballast?
 
toopy

toopy

Club Member
I know a UK supplied electronic dizzy (from a 280zx) should ideally have a 1.5 ohm coil, not sure if that's true for a 280z one if that's what you have, a 3 ohm will work just fine, but they generally have a shorter life span in combination with a leccy dizzy.
 
Farmer42

Farmer42

Club Member
I have a 280ZX E12-80 Dizzy on mine (the one with a matchbox module on the side of it) and initially had a 3ohm coil. I had the same issues with popping & banging and then swapped back to a 1.5 ohm 280ZX coil. Cured the problem instantly. If you have a 3ohm coil, I would suspect it has gone bad. First of all, check you have power from the ignition switch to the coil. Then check all the feeds through any ballast resistor. If all good, you will probably need a new coil.
 
Breakzero

Breakzero

Active Forum User
Thanks everyone for your info from what you have learned, I hope it is the coil. Should have one arrive today to test.
My bad I typo'd I actually have a 1.4 OHM coil! And have ordered a 3 OHM! I will order the correct one instead.

So it looks like this black box underneath is a ballast you all think? I've searched part number on it. And nothing comes up.
 
Breakzero

Breakzero

Active Forum User
Ok so after a different Google search I found my black box which is actually a G423 ignition module. They are sold as an ignition control module? GM motors or Fiat part!

So here is my wiring diagram and it appears I am not running a ballast.

I believe this diagram is correct... I did wire the car many years ago. The wires to tacho and ignition switch is where I believe they go without using a multimeter.
 

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toopy

toopy

Club Member
Got a picture of the top of the dizzy with cap off?

If there is a separate ignition module, is the the dizzy possibly a points version, converted to electronic with a 3rd party kit, like Lumenition for example.
 
Breakzero

Breakzero

Active Forum User
Rob Gaskin said:
And the module may be that Fiat part?
Click to expand...
Yes it seems that way. I just had the dizzy apart and cleaned it up. Believe it is a 280z dizzy. It's exactly the same as page 78 - 80 in the Haynes repair manual.
Called a transistor type.

Just tested coil again and I have 12v with ignition on. To the end of the king coil lead to dizzy.

I do have 1.5 ohm across coil positive to negative. So I think I can rule out the coil. (Also tested another new one).

So does it look like maybe dizzy failing now? As I have 12v to the dizzy in the lead but no spark.
 
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