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

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SquareRoot

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She's coming to life.... It's like ******* magic.. It was the throttle plate not opened up enough.

This is why I asked if you had touched the idle adjustment screw. I went thru this too. Idle adjustment on efi can be tricky until you understand how it works. Unlike a carb, the screw adjustment is only half the equation. The IAC actually does most of the work.

Make absolutely sure the butterflies are only resting on the idle screw and there is ZERO tension in the throttle cable at rest.

The ECU resets the tps everytime the ignition is cycled. More on this later.
I'm glad she's alive!
 

Vbb199

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Have to add here, yesterday night, after the truck had sit for nearly 24 hours, I jumped in, primed the truck twice, and it fired right up.

Idle "seemed" to take off, but I think all that was happening was it went to like, 1200 or 1300, it initially scared me because it's difficult to distinguish the difference between 1200 and, 1,000,000 rpms because the thing is SO DAMN LOUD.

But the idle leveled back out close to the 750 I set it at.
(had to fire it up for the misses, despite her saying it was too loud)

I should've gotten a picture of her with her ears covered. LOL


Might I add, the only reason I had to prime it twice is because I'm running gas out of a gallon jug, my gas tank is just too nasty. So I lose a prime everytime I remove the gas from the jug.
 

SquareRoot

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One of the things I really hated about MY Sniper was the idle always had a Dr.Jekyll- Mr.Hyde attitude. One minute it was fine and the next it was evil. Damn thing would take off at a stop light and damn near rear end the car in front of me. I had to put it in neutral for piece of mind.

What was Holley's answer when I called their tech line? You have EMI, move the wires, wrap the wires, blah blah blah. The answer to every problem is EMI.

My solution was the dumpster. Hopefully yours gives you miles of smiles. :)
 

Vbb199

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Seeming like so far there's no worries. But it hasn't ran for more than 1 minute at a time yet.

Just multiple 1 minute intervals.
 

Vbb199

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So you just turned the idle screw off the stop and it started?

I want my money back.


I know right?

Alot of fuss just for a idle screw.

It was one of the first things I had in my head... But I thought, surely the efi would meter its own idle.

Evidently not.
 

Vbb199

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Needs air too.

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That was probably lied out in the instructions somewhere, but I think Im missing a page or two. They got lost somewhere in between when I unboxed it a year or 2 ago, and now.
 

bluex

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I know right?

Alot of fuss just for a idle screw.

It was one of the first things I had in my head... But I thought, surely the efi would meter its own idle.

Evidently not.


It does meter its own idle, you have to set the baseline though, just like a carb.....
 

SquareRoot

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And your warranty is up. They give you like 90 days or a year and like most of us, we buy the **** and it sits for a year or more before we install it.
 

Vbb199

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It does meter its own idle, you have to set the baseline though, just like a carb.....


Lemme clarify, "meter the idle all by itself" lol.

I've worked with chevy tbi systems before... I should've known I had to set base idle before the IAC would take control.
 
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bluex

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And your warranty is up. They give you like 90 days or a year and like most of us, we buy the **** and it sits for a year or more before we install it.

While true, if you call them an explain the situation without trying to BS them or raising cain right off the bat most of the time they will still take care you even if the warranty expired while it sat in the box....
 

bluex

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Lemme clarify, "meter the idle all by itself" lol.

I've worked with chevy tbi systems before... I should've known I had to set base idle before the IAC would take control.

Ya I didn't wire my a/c request through the sniper an it can still control the idle for the a/c compressor cycling, my e-fan coming on etc. Once dialed in it should be able to compensate on its own just fine.

If you add a/c the function is there for it to automatically bump the idle speed when the compressor request signal is high. I just don't use it at the moment, but I probably should as a little more rpms would probably help the efficiency of the system overall.
 

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