Hi Everyone,
Long-time listener, first-time caller. I am the owner of a 1979 F150 short bed 4x4 (4-speed manual trans). My intention when I bought the truck from a guy from Oregon in 2015 was to make it my daily driver. The 400 M was rebuilt in 1995, and he said it was his son's daily driver until 2000, and put about 30K miles on it. (documentation of the engine rebuild came with the truck). The truck gets here, and has a bunch of electrical issues (mainly in the dash/gauges, but also lighting). I got those sorted out, but the truck had been sitting for a while, and the two-barrel carb needed to be rebuilt. So, rather than putting money into the 2bbl, I saved up and bought the Holley sniper in-tank retrofit kit (Edelbrock performer 4bble manifold), along with the Hyperspark distributor, Sniper Coil, and ignition box. It initially drove quite well, easy starts, easy cruising, no rich gas smell, but as I have been taking it out more frequently, it is now having some issues. It bogs down when I attempt to accelerate. I initially thought I may be having a vapor lock problem, because I noticed it would do this when it was warm. Well, now it does it when it is cool or cold as well. And, it didn't do it until recently. I am the type of guy who can install it, but when it comes to reading and understanding all of the parameters that come with tuning it, I am a novice. I have determined the loss of power issue is not a fuel delivery issue. Any advice would be much appreciated. Below is a list of all mods/maintenance done to the truck since I have owned it.

1. Yukon Ford 9" Trac Lock rear end
2. 1973-79 Ford Brake Upgrade (2004 F350 brake booster/master, Thunderbird calipers, 1979 F350 rear wheel cylinders, new brake lines)
3. Holley Sniper EFI (new 4bbl manifold, Intank retrofit kit, Hyperspark distributor, coil, and ignition box
4. New wheel bearings, drag link and tie rods

 

Try asking down on the engine forum that covers yours.

 

Will do, thank you.

 

As I understand it the Holley tech line (call in) is awesome, make the call and reach out to the pros. I did a little thread searching for "Holly sniper swap" and found all the below, reach out to fellow FTE members that have done that swap.

https://www.ford-trucks.com/forums/1...t=holly+sniper

https://www.ford-trucks.com/forums/1...t=holly+sniper

FiTech, but it has return line details that should work for a Holley EFI https://www.ford-trucks.com/forums/1...?highlight=EFI

https://www.ford-trucks.com/forums/1...?highlight=EFI

https://www.ford-trucks.com/forums/1...turn-line.html

https://www.ford-trucks.com/forums/1...injection.html

Awesome info on a 2wd 77 F250 460. Even though it a different site and a EB site to boot, TONS OF INFO. I mean detailed for sure.
https://classicbroncos.com/forums/sh...d.php?t=293349

U tube talk for days on Hollysniper. https://www.youtube.com/results?sear...lation++review

https://www.ford-trucks.com/forums/1...niper-efi.html

 

I'm about to convert mine to the same setup and in reading up on it ran across a couple tips that seemed to help others

1. O2 sensor fouled out? (Seems that can be a thing if truck runs rich or has a little oil coming through)
2. Have you tried a reset of the config (have it relearn your rig)?

 

I have the Holley Sniper 2300 (2 injector) and had a similar issue with mine. My co-worker suggested I check the fuel regulator, it's on the supply line side that actually on my throttle body. The fuel regulator comes off with four metric allen wrench set screws. I removed the fuel regulator and clean the fuel screen (had several small pieces of what appeared to be nylon tube. Re-installing it takes some pressure because of the O-Rings, but you'll be able to get it re-installed, just be patient. Suggest checking / cleaning before anything else and test driving it to see if it's improved. Obstruction/s increase the fuel pressure which affects the EFI performance.

 

Hi Everyone,
I thought I'd post an update on my issue. I cleaned the screen on the fuel pressure regulator as many of you probably have also done. Same issue persisted. I also ended up replacing the IAC module, as it was a $20 part (I found a Dodge OEM part for that) that is kind of known for acting up. That seemed to fix it for one single drive. When I started it up next time and drove it, same thing. I ended up completely wiping the tune that it had stored in it, wiped the firmware that was on it (I think it was from when I first purchased it a few years ago). Uploaded the newest firmware version. I then got back in the installation manual and set up all the parameters as it instructed to. I made sure that the Idle Air Fuel Ratio was between 13.5-15, the Cruise Air Fuel Ratio was between 13.5-15.5, and that the WOT was between 11-13. Additionally, I double checked to make sure that the IAC % was between 8-12% at idle. Props to this guy's video link below. It really helped me to understand how to set up the IAC. Bottom line, it runs great now. I hope this might be able to help someone else out.

 

Great to hear your rig is running good again and thanks for sharing the video, that was very informative.

 

Glad to hear your Sniper is back to good. I've mostly had good luck with mine, but it's starting to give me odd coolant and intake temp readings (coolant is super high and intake temps super low.)