Hello I have a 94 f250 7.3 that keeps shutting down it will idle all day but when you start driving it's done I had a leak in the fuel water seperator and I fixed it then I noticed some of the fuel lines going from injector to injector where leaking so I fixed and replaced them I also did a rebuild on a few of the injectors I have plenty of pressure when I'm sitting at idle but when I'm driving my fuel filter light comes on (replaced at the start of the problem) shortly after it acts like I turn it off what is wrong it's driving me nuts

 

It's an idi turbo sry I forgot to mention

 

Some of the more experienced guys will chime in, but kinda sounds like it's sucking air before the lift pump or the lift pump itself.

 

Fuel restriction might cause grief like that, first thing I would do is bypass ALL of the low pressure stuff by running a hose right to the IP. If it runs fine after that, there is a restriction, or perhaps a bad air leak somewhere between the tank and IP. If not, there's a problem with the IP.

My buddy's truck did something similar, then decided to not run at all, and it turned out to be a stuck tank selector valve. Restrictions tend to run fine then stall, air intrusion tends to cause massive hiccups and stalling. The reason for this is that with a restriction, fuel delivery keeps up at low load, then more gradually turns into a vacuum that starves the pump. With air intrusion, a consistent supply of air is getting pumped back to the tank, but when you use the available fuel up, it promptly runs air into the lines.

Not down to the last 1/4 in the tank right?

If running the IP out of a bottle doesn't fix it, my guess would be something governor related (inside injection pump). At that point I'd say that if you have to ask, it's probably smart to just source another IP.

Oh, and btw if you have a minor air leak between the lift pump and the injection pump, a bad lift pump will make it a LOT worse. The DB2 IP in these things has an internal vane type pump that will create negative pressure upstream in the low pressure system.

 

Ok so I should try running a direct line from the tank to the injector pump and it runs fine I'm sucking air if not then it's probably the injector pump well if it is the injector pump is there anybody near chillicothie ohio that may be able to rebuild one if not are there any recommendations

 

I don't think that's a good idea. The IP won't really suck fuel by itself; it either needs a pusher pump or a gravity feed tank.

I would replace the low-pressure transfer pump first. It's cheap($27), easy to do and a good first test. Once that's replaced, if you still have the problem, take a jerry can and run a piece of hose from that into the intake side of the transfer pump -- it's the side with the hose barb on it. Then try. If that works, you're looking at fuel tank issues. If not, potentially the IP.
I'd be much more inclined to think low pressure pump and/or tank issues, though.

 

I replaced the lifter pump but the one that it calls for is different then the one in it when I got it they said it would be fine because it comes to the same point just different angle (the arm this is what the guy at ford said) but when I put it in I wasn't getting fuel presure to the fuel heater

 

Are you sure you're getting fuel /to/ the pump?

I'd hook up a jerry can at this point -- just a length of hose into a can full of fuel, and connect it to the intake side of the pump.

 

A couple notes:
Your initial symptoms are definitely related to the fuel supply to the injection pump. I had similar issues when my lift pump crapped out.

The different type of arm on the lift pump is normal, there are two styles that are interchangeable.

Like Macrobb said try a length of hose from a can of fuel direct to the lift pump and see what happens.

 

you have solved the problem already...you have a fuel restriction...as the filter lite will only come on when the transfer pump in the ip, that can suck a vacuum strong enough to trigger the fuel filter lite. telling you that the filter is plugged or fuel line is plugged, or lift pump is bad,(junk stuck in the check valve in the pump).. or tank selector valve stuck half way...the ip can suck fuel from the tank, though two filters and fifteen feet of line, and a E pump with a blown fuse, won't do much but idle, made it home fixed the fuse.... it will pull from the tank but it was not designed too...

 

when putting the lift pump in, you have to get the arm under the cam eccentric otherwise it will not pump. to do this properly stuff the arm into the block pointing down, then let the pump flush with the block. you should feel a little resistance when the plunger arm hits the eccentric.