Fuel Injection, (starting problem)
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From: Independence, MO
Fuel Injection, (starting problem)
I have 87 5.0 EFI Problem: after it sets overnight or for a good while, when you go start it it , the engine has to spin a good bit before it fires up, not like most EFI's when you hit the key they fire up almost instantly, IT acts like it has prime back up then it fires up, otherwise it runs great. Anyone have ideas on what the problem may be?Thnx DW
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From: Wheatland, Mo
Fuel Injection, (starting problem)
Just out of habit, kinda like a diesel, I let mine sit until the EMMISIONS light goes out the I start it right up. But, what sounds like to me is that you may have an issues with the fuel lines holding pressure. Could be a small pinhole somewhere or loose fitting. Allowing just enough of a leak so that the fuel backs out of the line when the vehicle sits for a long time. But the fuel pump pressure is enough to keep it running once it is started.
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From: Independence, MO
Fuel Injection, (starting problem)
i dont have any external leaks that i can find, and there no gasy smell anywhere, i was kinda wondering if maybe there was a injector leaking after its turned off?? i did notice last time i changed the oil, the used oil smelled a little gassy?
any one else with any ideas? Thnx DW
any one else with any ideas? Thnx DW
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From: Wheatland, Mo
Fuel Injection, (starting problem)
Another thing to look at since you mentioned the injestors, is for discoloration on the intake manifold right at the point where the injectors enter. This will tell you if there is any leaking there.
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Fuel Injection, (starting problem)
Does your '87 have one pump or two? If it only has one then I can almost garantee you its the fuel pump. I had the exact same problem on my '90. Do yourself a favor and go buy a $30 fuel pressure gage and see what its reading on the fuel rail. Mine had only 26 psi with the old pump...(causing the hard starts) and jumped right up to 50 psi with the new pump. A Hayne's manual is a great source for running all the fuel system tests. 
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From: Independence, MO
Fuel Injection, (starting problem)
i have a Haynes Manual, and mine does have 2 pumps, low pres. in the tank and high pres. on the frame rail . like i said it seams to run great once its runing, it just dont start instanly after its sat for a while, But the fuel gage is on the shopping list for shure!! DW
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Fuel Injection, (starting problem)
Even with my bad pump it ran fine after I got it started too, just took three or four cranks to get going in the morning. The pump supplies more than enough fuel to run, a weak pump just can supply the pressure needed for quick starts. The static pressure test in your Haynes manual would tell you if you have a leak down problem. It should hold pressure within the acceptable range for at least one minute.
Mine starts on the first try every time now!!
Mine starts on the first try every time now!!
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From: Independence, MO
Fuel Injection, (starting problem)
I'm gona check this out , hopefully it will be simple but with my luck the whole thing will blow up! 
Thnx for the insight DW
Thnx for the insight DW
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From: Cypress, CA
Fuel Injection, (starting problem)
DW: My recollection is that the Ford fuel pumps have a check valve to prevent the "bleeding back" - otherwise hold the pressure to the injectors. The suggestion to hook up a fuel pressure guage to test the pressure while your truck is cold is a good idea.
Good Luck and keep us posted
Russ
Good Luck and keep us posted
Russ
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From: Independence, MO
Fuel Injection, (starting problem)
( BIGRIC) Is there a trick for getting to center bolt on the upper intake ? the one that sits on the pasenger side under the plenium, where you cant get to anything. ??
??
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From: Round Rock, TX
Fuel Injection, (starting problem)
Use a long extension (or two shorter ones) and stick it straight down between the runners; it will get in there. By the way, that bolt has a torx head since a hex head socket wouldn't fit down that hole. I'll get you the size of the torx later this evening.
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From: Independence, MO
Fuel Injection, (starting problem)
Well that just figures, Iknew you had to go thru that hole somehow but my socket would not go through it, Thanks alot! i couldnt tell it had a torx head on it. 
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From: Independence, MO
Fuel Injection, (starting problem)
PATIENT: 87 Bronco 5.0 EFI
PROBLEM: after it sits overnight or for a long while it's hard to start, the motor has to spin a few times b4 it will fire up. other wise, it runs great its had recent tune-up, (plugs,wires, fuel filter.ect.) it does okay after it cranks the first time. useing my haynes manuel , i put a fuel pressure gauge on the rail, and tested the regulator, pres. eng off, pres. eng running, pres. w/vac line connected and disconnected, and did a static pressure test first clamping off the return line and the by clamping off the pressure line. all per the haynes man. here's the results:
eng. off: 40psi
eng. idle 30psi vac. on
end. idle 40psi vac. off
static pressure test according to my book, it should loose no more than 5psi in 1min. it dosent but it will leak down after 45min / 1hr. but soon as you switch the key on pressure jumps back to 40psi.
any ideas or sugestions, I wana shoot it!!
PROBLEM: after it sits overnight or for a long while it's hard to start, the motor has to spin a few times b4 it will fire up. other wise, it runs great its had recent tune-up, (plugs,wires, fuel filter.ect.) it does okay after it cranks the first time. useing my haynes manuel , i put a fuel pressure gauge on the rail, and tested the regulator, pres. eng off, pres. eng running, pres. w/vac line connected and disconnected, and did a static pressure test first clamping off the return line and the by clamping off the pressure line. all per the haynes man. here's the results:
eng. off: 40psi
eng. idle 30psi vac. on
end. idle 40psi vac. off
static pressure test according to my book, it should loose no more than 5psi in 1min. it dosent but it will leak down after 45min / 1hr. but soon as you switch the key on pressure jumps back to 40psi.
any ideas or sugestions, I wana shoot it!!