HELP Holley super Sniper 4 bbl woes, 502 ci big Block

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DoubleDingo

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If it ran and then died a few seconds later, maybe starved for fuel? But only starved after it runs
 

Vbb199

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According to the interwebz.... Other people who faced the problem of a brief startup followed by death is due to the tach tignal not being synced to the holley....

I just reloaded the software actually.... Let me. See if the tach is synced up or not.


Tach is synced up.

Now I just have to wait on the charger to rejuice the battery.

To answer you @Bextreme04 i do have big gauge grounds from the battery .. Like 00 gauge or whatever, the **** that's 1/2" thick or so.
 

Bextreme04

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Nice! If it starts up, make sure you get a good video of it! I really want to see that big boy eat
 

SquareRoot

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Amazing. Get home, hook the efi up directly to the battery, bump the starter, this bad bitch started to run... Then..... Shut off. Lol


Man it sounded f'n nasty.

Have you messed with the idle adjustment screw? I mean at all, have you even touched it?
 

DoubleDingo

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Vbb199

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No, I haven't touched the idle screw.

Should I?


Also. I'm downloading the latest firmware, so that way things can be extra extra confusing and **** me up.
 

Vbb199

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Firmware installed on the holley... Just thought that might help, as I understand it from @SquareRoot it comes with outdated software.

So... Here shortly I'm gonna try again.
 

Bextreme04

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No, I haven't touched the idle screw.

Should I?


Also. I'm downloading the latest firmware, so that way things can be extra extra confusing and **** me up.

I saw a forum thread(not this forum) that had the coil signal missing, no ignition run voltage, and idle screw set too low as all being possible causes for the exact problem you described. Apparently the holley will not allow any fuel delivery except the initial prime if it doesn't see a tach signal(which apparently should come from the "coil" , not the "tach" wire).
 

Vbb199

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I saw a forum thread(not this forum) that had the coil signal missing, no ignition run voltage, and idle screw set too low as all being possible causes for the exact problem you described. Apparently the holley will not allow any fuel delivery except the initial prime if it doesn't see a tach signal(which apparently should come from the "coil" , not the "tach" wire).

No sarcasm when I say this.... You tell me what it means...

Think I should try the coil negative wire instead of the tach wire??????

You must be registered for see images attach
 

Vbb199

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Closer shot of the diagram.

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Vbb199

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On the coil, I have brown, red and black.

If I was to tie into "coil negative" should it be the black wire I assume?
 

DoubleDingo

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Closer shot of the diagram.

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The yellow according to their diagram, if that's what you're using you should be okay, No?
 

Vbb199

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The efi's crank signal lead is yellow.

My hei has a pink wire for ignition 12v, brown for tach, and then there's the actual coil wires that go to the pickup, which are red, brown, and black.


Currently I have the crank signal wire (yellow on the efi)
Tied into the hei dizzy's brown wire labeled "tach"


But accord to Mr. @Bextreme04 findings (which I welcome), I need to be feeding the crank signal from the negative wire on the coil, rather than just the output labeled as "tach"
 

DoubleDingo

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81-C20 Silverado Camper Special-TH400-4.10s; 65-C20 with 4:57 gears and Borg Warner Overdrive
Engine Size
Carb'ed Vortec 350; 1972 L48 350
The efi's crank signal lead is yellow.

My hei has a pink wire for ignition 12v, brown for tach, and then there's the actual coil wires that go to the pickup, which are red, brown, and black.


Currently I have the crank signal wire (yellow on the efi)
Tied into the hei dizzy's brown wire labeled "tach"


But accord to Mr. @Bextreme04 findings (which I welcome), I need to be feeding the crank signal from the negative wire on the coil, rather than just the output labeled as "tach"

Isn't it the same thing? Meaning, isn't the tach signal coming from the negative? Or am I missing something? If your wire is brown, the efi unit won't know.
 

Bextreme04

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The efi's crank signal lead is yellow.

My hei has a pink wire for ignition 12v, brown for tach, and then there's the actual coil wires that go to the pickup, which are red, brown, and black.


Currently I have the crank signal wire (yellow on the efi)
Tied into the hei dizzy's brown wire labeled "tach"


But accord to Mr. @Bextreme04 findings (which I welcome), I need to be feeding the crank signal from the negative wire on the coil, rather than just the output labeled as "tach"

The diagram shows it going to Tach, so I think you should be good... they might have meant coil(-) on a different ignition setup. I'd try it like you have it with the things you have fixed first, then try switching to the negative coil hookup as a last resort
 

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