This all started when the truck wouldn't start on it's own a little shot of starting fluid and it would fire right up and run fine.

I changed the lift pump and that fixed the problem.

Now it stumbles at part throttle it is the worst around 1500 rpm.

If I step on it while it is doing it it seems to come out of it and will run fine

Does anybody have any ideas what it might be?

Thanks in advance
Curtis

 

Have you changed the fuel filter?

 

thats where i would start.

do you have any smoke when it stumbles?

 

Sorry I forgot to mention that I changed the fuel filter along with the fuel pump.

I cannot see any smoke, but that does not mean anything.

Thanks
Curtis

 

Timing too far advanced?

 

i had the same problem and it turned out to be the thrush bearing goin bad in my turbo causing it to leak and shortly after i blew my turbo _______________ 1993 d250 ,w/ 3200 gsk,big sticks, 14mm studs,head gasket,timing bumped,and 96mm schweitzer turbo 65psi

 

How could the timing move so suddenly like that?

How should I check to see if the turbo bearings are going?

Thanks
Curtis

 

Just throwin it out there.

check your fuel supply side for air leaks.

 

just check for any travel in the shaft . some up and down isnt soo bad but you dont want any in and out movement

 

Sounds to me like it is still sucking air in somewhere. How's the fuel heater gasket?

 

Didn't check the the heater gasket, the wires are ripped out of it, so I might as well take it off and leave it off

Thanks for all the info I will take a look when I get a free minute and let you know what I find.

Curtis

 

I think you just found you're problem. You could try for now filling the plug void with some sort of sealer.

 

the wires have been ripped out since the day I bought it there aren't any holes in it the wires are broken off at the heater. But when it quits raining and warms up a little I will pull it off. (does any one know the part # for the short fuel filter nipple?)

Thanks
Curtis

 

Well I got around to looking at the truck today I don't think it is air getting in, could it be pieces of the shutoff plunger getting stuck in various parts in the injection system?

The shutoff hasn't worked in a couple of months (been using a pull cable till the new one arrives)

Thanks
Curtis

 

Put a piece of clear line in and make sure before you throw money at it.