ok i found the year of the engine its a 1991
now i have this problem to deal with. i had this post under the "how to tell the year of an engine " and i started this one so it would not be under a question that was found out.

i can start the truck with out any white smoke at all even thought it is below freezing here in ohio. it starts right up and idels fast untill the fast idel kicks down like it is suposed to do. it will idel all day long with out stalling out.
but when i go to pull away i can only go about a 1/8 mile before it stops abruptly (just like i pulled the fuel shut off conector off, its that fast) this truck was running great for the four days i had it then this.

things i have done to remedy ths problem that haven't worked

1 drained the water/feul seperator - fuel filter

2 replaced the water/fuel seperator - fuel filter

3 siphoned out all of the fuel he had dyed fuel in it when i bought it and replaced it with winter blend from bp

4 ran it at idel for a hour to get all of the red fuel out of the lines and to let the cleaners do the their stuff (i also did this to make sure the block was hot and tried to drive it away. i made about 300 yards before she died. it took about 45 secounds of cranking to get her to fire over agian)

5 checked all of the glow pugs with an ohm meter all were with in specs posted in the sticky on this site (great site by the way)

6 cleaned the contact where the fuel shut off is on the tylidne injector pump found no corision but thought mayby a lose conection?

7 checked for any fuel leaks in the new snow found none not even a oil leak anywhere.

8 check all of the fuses for a blown one found one and replaced it still the same problem 25 amp in the upper left corner of the fuse box. i dont have the wiring diagram to figure out what this one does but with the truck ideling and i pull the fuse the truck still runs so i dont think it has to do with the fuel problem

9 i bled the injector lines in case i traped some air when i did the filter change



i am doing the fuel test right now to verify what i came up with to make sure i did it right i will post the reults soon. thanks, brian

 

ok i did the fuel test and i got less than 1/3 of a pint in ten secounds and the fuel presseure is 3 to 4 ponds with ten secounds of starting with the fuel cyleniod pulled so the truck wont start

as i see this i will need to replace the lift pump on the side of the engine please let me know if this is correct. thanks agian, Brian

 

Does the truck start back up quickly and easily or is it difficult to start. Does it quit again right away or is it okay after it starts If it starts easily I would check for electrical problems at the pump. install a test light or volt meter to the power supply at the pump and drive it see if the voltage drops when the truck quits. If it starts hard it could be getting air in the system. I just noticed you cranked for 45 seconds, that could be sucking air, probably the hardest problem to find. Any injector or hose in the system could be the culprit, they usually dont leak fuel they just suck air or let fuel drain back to the tank creating an air pocket. I would check for blockage and power problems first then if you cant find a problem suspect air allthough most of the air problems I have had will start run for 5 to 30 seconds and quit. There could also be blockage at the fuel pickup in the tank, the best way to check this is to install a fuel pressure gauge and drive it, I tee it into the rubber line at the lift pump and let it sit under the wiper blade and drive the truck, in my experience there should be around 7 inches or less of vacuum while driving at around 12 to 14 inches of vacuum the truck will quit. I'm not sure that the supply pump is your problem it sounds a little weak but they don't usually stop pumping then start again. If possible lets try to find the problem before we start replacing parts. hope this helps

 

cool i will try this to see what happens. i did not think a fuel line would let air in and not fuel out but this definatly sounds like it could be a problem to look into. when i did the fuel quantity test i noticed a lot of air bubbles with the feul as it flowed out o the clear plastic line the i used to fill the measuring cup with. can a fuel lift pump run a truck at idel but not keep up with it if the rpms go higher in the 2000 rpm range?
i am going to back track the fuel system tonight and pull eack line and check with a vacume pump and gauge to look for line breakes. thanks for the idea will post later when i find any of them.Thanks agian, brian

 

I had one that had leaves in the tank I think I used a dirty container or something. Drove me nuts for weeks. I finally found the problem with a pressure gauge installed before the lift pump. I have never had a supply pump do that if it is weak you will usually just loose power not get air and they most commonly just dump fuel into the crankcase. I've found most of my air leaks on the little lines that go from injector to injector and around the fuel filter, this lets the fuel flow back out of the filter and back to the tank replaceing it with air. I think I read somewhere on the form that Ford reccomends plugging the little rubber line that goes from the filter housing to the rail but reasurch it first or someone may post more to your situation. I know some people that park their truck down hill to prevent this problem and if they forget and park uphill it will suck air and quit. good luck

 

thanks for th info i will check the crank case for fuel to. i just started on the little lines nothing yet. when i ran the truck at idel and i let some fuel out of the shraeder valve i noticed a lot of air in it so i know that there is air comming from some where, just a matter of time before i find the little bugger. Thanks agian, brian

 

I think on that truck there is a steel line that runs allong the cross member to the lift pump, this is also a good place to check, if it hasn't been changed already, check it closely from end to end. If it is severely rusted push and pull on it a little if it breaks thats probably it!

 

The steel line that runs all the way from the tank to the fuel pump could be rusty and pitted enough to leak air.

O rings in the connectors can also leak air.

The fuel pickup tube in the tank is also another place that is a common culprit, they crack and suck air somewhere between 1/4 and 1/2 tank of fuel. No problems when the tank is full, all kinds of problems when the fuel is low is usually the indicator for that.

Air will go places fuel will not, the air molecules are much smaller.

 

Also if the line from the filter header to #1 injector is hooked up clamp it off or remove it from the header and plug both exposed ends, see if that helps. Check the rubber fuel line at the lift pump too.

 

ok i found the problem so far, two of them actully. the #1 and #2 fuel return tee's had cracks where the ruber hose connects to them. when i touched them the just broke at the connection points. i am going to epoxy these holes closed with the tees off of the injectors and close off the line that would go back to the fuel water seperator to see if the remidies the problem. i will get new tees monday to replace the old ones. i am thinking of replaceing all of them. but one question if it is recomended to close these off canthese just be eliminated buy epoxing all of the tees shut. would like some input, Thanks agian, brian

 

ok i found a new kit at nappa and i just got it and i will install it next. will post what happens. thanks, brian

 

If your lift pump is bad put in an electric fuel pump,I put a Facet on mine and my drainback problems went away,its also helpfull at fuel filter changes,you dont have to crank and crank until the filter fills up,just turn the key!

 

i will keep this in mind. it sounds like a great idea and a goog up grade to. the injectors and the tees are going a lot better than i thought i am almost half way and there were a lot more air leeks than i thought. Thanks, brian

 

i have all of the tees onm and now i am having trouble primming the punp and injectors so this is making me think that i do have a bad lift pump now any thoughts

 

you need the tees that go from injector to injector to stay hooked up they allow the injector to bleed out excess fuel and fuel that leakes by internally. If you block off the the injector tees the injector will not function properly it will blow the oring seals out of the tee or crack the tee. it takes around 2000lbs of pressure to fire (open) the injector. The only line you can plug is the one that goes from the filter housing to the injector rail (tee) but the injectors need to bleed off from one to the next all the way back to the tank.