IT'S ALIVE!!!

[68rustang]

EFI Project - IT'S ALIVE! I have a few questions...

As of 3/2/06 12:23 AM EST my 68 EFI project RUNS! Idle is a little rough, I think one or more injectors are sticking. But it runs and it sounds WONDERFUL! I will post more in the morning I have to be at work in 6 1/2 hours and need to sleep.

:SNSign:

Should the fuel system maintain pressure when shut off or should it bleed down to zero?

 

[66ford289]

When I pulled a 460 out of a F-250 the manual called to relieve the pressure from the fuel lines so I would say that it does hold pressure afterwards. Eventually it probably would bleed down.

 

[iskwezm]

it will bleed down after a while(few hours)

 

[68rustang]

That is pretty much what I thought. My situation is that the pump will build approximately 40 psi while it is running and it has no problem maintaining it. However as soon as I shut the key off the pressure bleeds down to zero in a matter of seconds. I don't have any obvious leaks and the engine is running smoothly. Where the heck is the fuel pressure going so quickly?

 

[66Runt]

Fuel pressure regulator is a common leak down point

You might check that. Sticking fuel injectors would also allow pressure to bleed down rapidly.

Good luck,

Scott

 

[red65]

Congratulations rustang! Feels good, huh? My EFI fuel system bleeds pressure off within a few minutes. I worried about it at first, but it doesn't appear to be a problem. It probably just leaks back against the fuel pump, which isn't really built to maintain pressure (I use a T-rex inline). It should build pressure in a fraction of a second when you fire up the fuel pump - not a big deal that it bleeds off when it's not running.

 

[68rustang]

FPR, You might check that. Sticking fuel injectors would also allow pressure to bleed down rapidly.

The regulator was the first thing I checked. Usually if they are "bad" fuel will leak past the diaphragm. I suspect the injectors and have ordered caps, seals, and flters to rebuild them.

Congratulations rustang! Feels good, huh? My EFI fuel system bleeds pressure off within a few minutes. I worried about it at first, but it doesn't appear to be a problem. It probably just leaks back against the fuel pump, which isn't really built to maintain pressure (I use a T-rex inline). It should build pressure in a fraction of a second when you fire up the fuel pump - not a big deal that it bleeds off when it's not running.

Heck yeah it feels good. Especially since everyone was telling me EFI was too much trouble and just carb it. Now they have all kinds of questions on how to set theirs up I am not really worried about the pressure yet. They only thing that concerns me is it doesn't quite make 40 psi on the initial cycle, it doesn't have any trouble starting and runs fine and maintains 40 psi. it just seems like it is barely making it.

It runs, my wiring works, I will do final trouble shooting when it is ready for the road.