EFI dies after road trip

[BroncoinAlaska]

Been driving the bronco longer and longer distances breaking in the EFI so I can use it as my daily driver. It is running better than ever. It has good fuel pressure 40psi, and I have been chasing down all the smaller noises and potential problems. Untill it left me walking 3 miles from home today.
I took the bronco on a longer trip as I am trusting it more, 40 miles round trip for lunch. I put ten gallons in befor the trip. It worked flawlessly to lunch and almost all the way home. Then five miles from home it started missing then sputtering. Then at a stop sign it just died. It would crank, fire then die. I checked the gas cap and filter that I have on the BCB tank vent it was half full of fuel. I could hear the pump prime each time. Checked spark, OK. I was pretty sure it was no fuel situation. I cranked it one two manny times and started to get the solenoid click.
So I towed it home and I am charging the battery. I am thinking it is the pump in the BC Broncos tank. Any other ideas?

SPECS:
Ford 5.0 GT40X crate motor
BC Broncos 23 gallon tank
BC Broncos hard fuel lines and braided lines with fuel pressure guage
24lb ford racing injectors
Matched MAF
Aeromotive adjustable fuel pressure regulator

 

[Viperwolf1]

Check fuel pressure. This is one example when a permanently mounted gauge could help immediately ID the problem.

 

[BroncoinAlaska]

I have BC Bronco fuel guage with their braided line kit. Prior to the trip the guage read 40 psi. Fuel pressure was low when I checked it at home after towing it. It was below 20psi. I am thinking something got hot.

 

[Broncobowsher]

That sounds like a fuel pump that is either starving/caviating/vapor locking or going bad.

Just for giggles, when that happens try pinching off the return line. I expect no change when pinched. If the pressure does go up, you have a regulator that is going bad. No change in pressure, back to the pump.

 

[BroncoinAlaska]

Just fired up the Bronco in the garage. Fired right up! Solid 39-40 psi at the BC Broncos guage.

What could be the cause of the bronco dieing after the road trip?

 

[broncnaz]

Bad fuel pump. Once it heats up it onl longer pumps like it should.

 

[BroncoinAlaska]

Bad fuel pump. Once it heats up it onl longer pumps like it should.

If so it will be the third pump I have had to get from BC Broncos. The first one poped/ruptured the submersible line in the tank. Maybe with a new pump the gas guage will work?

 

[Lmfp]

Are you sure your not getting vapor lock? Was there any pressure when opening the gas cap? I know how much dropping these tanks sucks so it could be wishful thinking...

 

[rdanford]

I too am having the same issue with the fuel pressure and in-tank pump....I'm on my 2nd pump so far and dropping my tank again this weekend...keep us posted on what you find out

 

[BroncoinAlaska]

I am pretty sure I am not getting vapor lock. I have a couple of holes drilled into the stock cap. Plus I did not hear any popping or giggling in the tank. Plus when I opened the gas cap there was no pressure built up.

 

[DirtDonk]

How long did you have to crank it before the battery died completely?
If you have a faulty charging system, when your battery gets below a certain threshold, your electronic EFI system will not be happy.
Frankly, my feeling is that if you have enough power left to crank the engine over even a few times, you should have had enough power to run the electronics without issue. But I have to bring it up as a possibility anyway, since I've seen it happen.

Once, on a return trip from the mountains, one of our group had a failure of his charging system and we had to swap batteries every half-hour or so of driving. The engine would start to sputter, we'd pull over and swap batteries with my secondary, then while it was charging up for the next half-hour or so, it would be ok to run his rig until the next swap.
We got home that way, but it was certainly a pain. And it certainly let him know just as soon as the power level reached that happy-minimum!

Worth a look at least?

Paul

 

[DirtDonk]

I am pretty sure I am not getting vapor lock. I have a couple of holes drilled into the stock cap. Plus I did not hear any popping or giggling in the tank. Plus when I opened the gas cap there was no pressure built up.

Vapor lock is not very common with an EFI setup with a return system I don't think. It's still worth thinking about, but I don't think I've ever seen that happen.
Closest thing to that would be a failing fuel pump that just can't pump when it gets hot. Might have the same symptoms, but from a different source.

Even so, I don't think you'd see a vapor lock issue by pressure buildup in the tank. If anything, that buildup would help mechanically push fuel up to the engine, where it would be available for use.
If it's truly vapor locked from feeding into the engine though, it would only be between the return line and the engine.
Where is your return? Are you running a stock-ish Ford setup with the return built into the fuel-rails and pressure regulator? Or something else?

And I could be wrong, but I don't think drilling holes into the cap of an EFI equipped rig is a good idea. Just a hunch though. No real knowledge on the subject.
Maybe one of the experts can comment on that. Maybe it's no big deal, but it's worth knowing.

Paul

 

[broncnaz]

Drilling holes in the cap will ensure its vented but really not a good idea vapors escape vapors mean explosion in the right conditions hoe you dont park in a garage.
While fuel pumps shouldnt go bad so quickly nothing is made like it used to be so it happends. You might want to find a similar pump that can be substitued so you dont have to wait for a replacement in the mail.