Intermittent Fuel Leak at Quick-Disconnect on Gen 2 Coyote Fuel Injection Rail

[JIMLAND]

About a year ago I started my car and soon smelled fuel. Pulled over and lifted the hood and saw fuel dripping for the fuel line quick-disconnect at the fuel injection rail. I disconnected it and reconnected it and it stopped leaking. Well, just yesterday I took the car out and again smelled fuel and again found the quick-disconnect leaking and a puddle of gas on top of the engine. I reconnected it and it was still leaking. Took several reconnecting before it stopped. Drove it home immediately and need to fix this big safety problem before I drive it again.

Has anyone had this problem and if so what did you do about it?

I would like to eliminate the quick-disconnect but looks like the only way to do this would be to install a new fuel rail with a AN fitting instead of quick-connect fitting for about $300. Any other ideas?

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[Mastertech5]

I would suggest replacing the fuel line and quick connect fitting.

[edwardb]

I don't have any experience with the quick disconnect fitting so no help there. What I have used on my two Coyote builds is a Ham-Let Stainless Steel 316 Let-Lok Compression Fitting, Adapter, 3/8" Tube OD x 37 Degree Flare. These go right over the 3/8" inlet and give you a -6AN connection. Rated for something in excess of 1,000 PSI, so very robust. I get them from Breeze. https://breezeautomotive.com/shop/fitting-3-8-od-tube-to-06an-male-316-stainless-steel/.

You'll have to change your fuel supply line to something different obviously. I use flex SS with -AN fittings. Certainly no need to replace the entire fuel rail. I agree this needs to be fixed before driving or even running the car again. That's an engine fire waiting to happen.

[facultyofmusic]

Are those the lines that came with the FFR kit? What's on the other side? I didn't use mine so if I have that part I can mail it to you.

[Railroad]

Do not bother getting or using the disconnects provided by FFR. Mine did the same leaking. I replaced them with a name brand from an auto parts store. NO MORE LEAKS.
Talk about scary, seeing that fuel spraying on top of a hot engine. I too could wiggle the disconnects and would stop or reduce the leak.
I threw all the FFR disconnects in the trash. I did not want to risk them getting used anywhere.

[Alan_C]

For my Coyote install, I am using these fuel rail adapters from Russell. Just me, but the idea of running plastic fittings and line seems like asking for problems. I run PTFE lined SS braided line.
With the safety of you, your car and your passengers in mind, I would look for a different solution for the fuel lines.

https://www.summitracing.com/parts/rus-644123

[Dgc333]

For my Coyote install, I am using these fuel rail adapters from Russell. Just me, but the idea of running plastic fittings and line seems like asking for problems. I run PTFE lined SS braided line.
With the safety of you, your car and your passengers in mind, I would look for a different solution for the fuel lines.

https://www.summitracing.com/parts/rus-644123

FWIW, virtually every new vehicle on the road uses plastic quick connect fittings and at least part of the fuel lines are plastic too. They have proven to be very reliable.

[Alan_C]

FWIW, virtually every new vehicle on the road uses plastic quick connect fittings and at least part of the fuel lines are plastic too. They have proven to be very reliable.

No doubt quality plastic line and fittings will work, however being a somewhat paranoid retired engineer, the stuff just looks cheap. Compared to quality AN PTFE hose and fittings I am sure the plastic stuff is far cheaper. We can all chose what level of quality of parts we put in our car. However IMO, the fuel and brake systems are not aspects of these cars I would be willing to say oh these cheaper parts are good enough. We put so many hours of work into our projects, that a little more money spent on the best quality components in critical systems is worth the price.

[Railroad]

I feel it is appropriate to call attention to the fuel tank filler tube grommet in this discussion. It is of poor quality, as the quick disconnects and will fail within months of exposure to gasoline.
I doubted posted info relevant to this serious issue, but did find it to be true.
Buy the Ford brand grommet and dispose of the one shipped with the kit.

[Al_C]

Do not bother getting or using the disconnects provided by FFR. Mine did the same leaking. I replaced them with a name brand from an auto parts store. NO MORE LEAKS.
Talk about scary, seeing that fuel spraying on top of a hot engine. I too could wiggle the disconnects and would stop or reduce the leak.
I threw all the FFR disconnects in the trash. I did not want to risk them getting used anywhere.

I agree with what Railroad says. This happened to me, too. I replaced the fitting with another brand. I'll look and see if I still have the original package, as I think I bought a spare. No problems since then.

[JIMLAND]

Are those the lines that came with the FFR kit? What's on the other side? I didn't use mine so if I have that part I can mail it to you.

The plastic fuel line with the quick connect came with the crate Coyote engine and fuel pump I got from Mike Forte. It worked great for a couple years but for whatever reason it leaked twice in the last year. I will have to get under the car and follow the line but I believe it connects to the fuel filter but don't remember what type of connector is on the other end.