2F HOLLY SNIPER EFI

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In regard to your plumbing pics.
I got the base unit and not the kit but looking at the kit, it comes with 3/8 ID hose and I am sure the fittings on the pump and filters are also 3/8. Where you clamp the hose onto the existing hard lines is of concern. The stock hard fuel lines are 8mm which is almost exactly 5/16. Clamping a 3/8 ID hose onto a 5/16 tube is risky for sure. Also, you should not put a hose onto hard tube unless it is beaded. If you’re going to use hard line it should be 3/8 OD which also matches up with -6AN fittings.
So it’s basically extend 5/16 hard line. Or remove the original 5/16 hardline completely and run 3/8 hose from the efi to the tank?
 
I used hotrod fuel hose on my project and built new lines in 3/8 with an6 fittings. Their prices are fair, quality is good, and I'm really happy with it. It's a ls engine with the holley terminator computer, but also is 60 psi.
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If the ecu is reading the signal from the negative side of the coil then it will get a rpm based off of the cylinder # parameter you entered in upon your initial programming. This is a pretty simple setup and it should be pretty easy to verify all the different ingredients for success.

Put a multi meter on the yellow wire and see what sort of voltage and continuity your getting. Audible continuity will be fine. Don't even worry about polarity, you just want to make sure you're getting an rpm input signal. Since it tires to start but doesn't it means your running off the prime only and the injectors never open.
I’m getting 12.02V whole testing the negative side of the coil where the yellow wire is hooked up to
 
If the ecu is reading the signal from the negative side of the coil then it will get a rpm based off of the cylinder # parameter you entered in upon your initial programming. This is a pretty simple setup and it should be pretty easy to verify all the different ingredients for success.

Put a multi meter on the yellow wire and see what sort of voltage and continuity your getting. Audible continuity will be fine. Don't even worry about polarity, you just want to make sure you're getting an rpm input signal. Since it tires to start but doesn't it means your running off the prime only and the injectors never open.
On the initial programming, I set the cylinder # to 6.

Also, put a multimeter on the yellow wire and its getting 12.02V
 
On the initial programming, I set the cylinder # to 6.

Also, put a multimeter on the yellow wire and its getting 12.02V
Holley Sniper is getting 60psi fuel pressure at the gauge. Still reading STALL in on position while cranking.

Will be calling Holley tomorrow toreturn and exchange the EFI system. Seems like the ECU may be faulty. Had a mechanic checkout my wiring. And it all checked out perfect.
This thing is driving me nuts
 
Holley Sniper is getting 60psi fuel pressure at the gauge. Still reading STALL in on position while cranking.

Will be calling Holley tomorrow toreturn and exchange the EFI system. Seems like the ECU may be faulty. Had a mechanic checkout my wiring. And it all checked out perfect.
This thing is driving me nuts
Glad see you're making progress. I hear Holley is really good and fast with warranty exchanges. Good luck with everything, let us know how it goes.
 
Glad see you're making progress. I hear Holley is really good and fast with warranty exchanges. Good luck with everything, let us know how it goes.
GOT IT WORKING! It was definitely a fried ecu from the factory. The new one arrived today! Installed it, and BAM! FIRED UP FIRST CRANK!.

Now I just have to figure out why its idling around 2400 once I fire it up. I set the idle in the wizard at 720..
 
GOT IT WORKING! It was definitely a fried ecu from the factory. The new one arrived today! Installed it, and BAM! FIRED UP FIRST CRANK!.

Now I just have to figure out why its idling around 2400 once I fire it up. I set the idle in the wizard at 720..
Glad you got it figured out. I was crusing along today thinking how nice some efi would be.
I hate that you had a bad unit. I hope it is an isolated incident. There is nothing I hate more than expensive junk.
 
Glad you got it figured out. I was crusing along today thinking how nice some efi would be.
I hate that you had a bad unit. I hope it is an isolated incident. There is nothing I hate more than expensive junk.
I completely agree. Was driving me crazy the entire time. Thinking I had done something wrong, when it was the unit.
 
GOT IT WORKING! It was definitely a fried ecu from the factory. The new one arrived today! Installed it, and BAM! FIRED UP FIRST CRANK!.

Now I just have to figure out why its idling around 2400 once I fire it up. I set the idle in the wizard at 720..
That's great buddy. I sort of suspected the ecu when you said you weren't getting an rpm signal. Glad Holley took care if it for you.
RPM will be adjustable with the screw on the side at the linkage.
One thing I recommend is reading the manual front-to-back, back-to-front... and than read it again. All the info is there, and it will help you understand thre whole learning process. One thing I suggest is carrying a spare TPS. They're sort of fragile, but cheap and easy to replace, so good to have on hand.
Thanks for following up.
 
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GOT IT WORKING! It was definitely a fried ecu from the factory. The new one arrived today! Installed it, and BAM! FIRED UP FIRST CRANK!.

Now I just have to figure out why its idling around 2400 once I fire it up. I set the idle in the wizard at 720..

It’s been awhile since I’ve been in my manual, but there’s a setup for the TPS and you want to make sure that the bell crank is returning all the way. Mine needs a return spring.
 
That's great buddy. I sort of suspected the ecu when you said you weren't getting an rpm signal. Glad Holley took care if it for you.
RPM will be adjustable with the screw on the side at the linkage.
One thing I recommend is reading the the manual front-to-back, back-to-front... and than read it again. All the info is there, and it will help you understand thre whole thinking process. One thing suggest is carrying a spare TPS. They're sort of fragile, but cheap and easy to replace, so good to have on hand.
Thanks for following up.
I did read the manual, but it said to wait until the engine temp reaches 160 before I turn the idle screw.

the issue is, the car idles at 2400 as soon as I fire it up. Should I be running at that high idle until the car reaches 160 then back down the RPM screw?
 
I did read the manual, but it said to wait until the engine temp reaches 160 before I turn the idle screw.

the issue is, the car idles at 2400 as soon as I fire it up. Should I be running at that high idle until the car reaches 160 then back down the RPM screw?

Ours tried to do that at first. We turned down and then did a final adjustment at temp.
 
Ours tried to do that at first. We turned down and then did a final adjustment at temp.
Did you turn the screw in as soon as you fired up the engine? or before?

I took a picture of what my hand held shows as soon as a fire her up!

IMG_9082.webp
 
Did you turn the screw in as soon as you fired up the engine? or before?

I took a picture of what my hand held shows as soon as a fire her up!

View attachment 2521461

As soon as we fired it up, but this video mentions adjusting before. Your battery looks like it needs a charge.
 
It’s not unlikely at all that the idle screw was simply screwed in too far upon assembly. I see no problem backing it out before or right after startup. The learning process won't begin before it's warmed up. And the learn process can always be restarted/reset anyway.
 
Just adjust it roughly while it's cold, then readjust after it's all warmed up.
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Just adjust it roughly while it's cold, then readjust after it's all warmed up.
Got the rig started. Turned down the idle while the car was running before the temp hit 160. because it was idling around 2000-2100 rpms.

Backed out the idle screw almost all the way out, and its still idling around 1600, and now my IAC% is all wacked out.
The frustration of just wanting to drive this thing around town.
 
What do you mean Wacked Out?
IAC is bouncing around, or just not between 2-10%?
If the IAC is closed and it's idling high, air is getting in somewhere. Throttle is slightly open, or you have a vacuum leak.

...vacuum line, PCV, Brake booster, gasket, manifold... lot of places for air to get in.
 

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