This morning, truck started fine. Its 3 miles to the main highway. I pull on the highway and Nail it. Truck gets to ~50 mph and falls flat on its face. Pull over and open the dump valve from aux to main(Fuel gage broke) Pull back on road, nail it again, Still stumbles on the OD shift

 

The first thing to do is change the fuel filter.

 

Just how old is that fuel filter?? Hey wannadiesel pm me back,thats one nice intake.thanks TBoling

 

Fuel Filter is < 3 Months old. Tank is perfectly clean (as of 3 month ago)
Fuel is purchesed from one dealer only, and it is at the terminal

 

I'd still change it.

 

new fuel lines, tank wiped clean with clean virgin lint free clothes; and you would still change it? I politely disagree. I'll sell the thing befor I change my fuel filters more than oil filters.

 

You might have had a bad fuel filter.

I personally don't know what the interval for fuel filter changes is. I should probably do it some time, along with my differentia fluid, and tranny fluid, and power steering fluid, and radiator coolant...

Anyways, wannadiesel's probably right. He's like my mother; once he makes a suggestion, the STARS THEMSELVES will reorient themselves to make that suggestion true. It's SO annoying.

It sure sounds like a fueling issue though. Maybe a lift pump? I'd think the lift pump wouldn't fade in and out like that, though.

Maybe it's an electrical issue with your lift pump. Hah! There's an idea. I've had all kinds of shorts on my truck that occur at all kinds of random times.

 

i had a fuel issue before:

"CHANGE THE FILTER"

GUESS WHAT???????
the filter was not the problem, neither was the tank. Please, lets stop with the automatic change the filter, its starting to sound like a dealership with " lets change the injection pump"

You arent helping diagnose the problem.
First you say: Change the filter.
Then: It must be a bad filter.
Tell you what, I'll pulll the filter and cut the can, if its not the filter. One of you pony up with a new fleetguard!


BTW: its not like I dont know my way around diesels. I was the tech for the Fairbanks-Morse ND 8-1/8 on the sub, and I have been to Woodward Govenor School. I am trying to dig deeper into what is causing this problem.

I did drive the truck another 200 miles today from Aiken SC to Charlotte NC with no issues, flat 75-80 the whole time I-77 and I-20 were clear.


My next step will be to install the Fuel PRessure gage sitting on the bench to help with diagnostics

 

''My next step will be to install the Fuel PRessure gage sitting on the bench to help with diagnostics''

Good idea. Mine was pulling the same routine when my LP was failing. My guess is by the time you get to O/D on a hard romp, you've just plum run out of fuel, yet the lame LP will provide just enough to cruise at a moderate HP level all day. It happened mostly on the uphills with mine, when I was asking a lot of the engine. Keep us posted.
greg

 

ok you don' want simple, whats the fuel pressure, before and after the filter, whats the boost, any reduction, whats the egt, any reduction, what the hp side reading,to injectors. whats the kw/h at and after the od shift. awaiting numbers for further evaluation.
Clark

 

sorry, had an absolutly terrible day. should not even have responded. I shot the old f-m military gen engines in alaska and it was hell getting info to help by remote.
Clark

 

I'm all for more info (How many of you have your own 1600 HP Stuska Engine Dyno sitting in the garage)

Unfortunately I dont have the EGT Data, or the Fuel pressure data

And I think our computer is too freeking primitive to hook up a data logger to it.

I do think I need to adjust the TV Cable, because it takes to long to make the OD shift, almost like the tranny is easing itself into gear

 

I don't know wth your problem is but Wannadiesel only suggested changing the fuel filter because, A: could easily get a batch of bad diesel to clog it (no matter where it comes from) B: it could be faulty C: Its only like $15 and if it fixes your problem then its done!
Sounds to me like your problem is with either contaminated fuel system (lines,tank, filter, or ip). or it could be bad lp or the only other thing could be injection pump. Doesn't sound like something a bad injector would do.

With the information you gave in your first post Wannadiesel gave you the best advice he could!

 

thanks for the help(edit) Wanna. kept me from looking to bad.
Clark

 

Banzai- When diagnosing, I always start with the cheap and simple stuff. From your sig, I have no idea of your diesel experience or skill level. Your next step of checking fuel pressure is exactly where I was heading before you got your knickers in a twist. The problem certainly sounds like a fuel restriction - and not everybody has a fuel pressure gauge on the bench. That's where my repeated suggestion to change the fuel filter comes from. In my experience, when these trucks bog or die out under load, it's either lack of fuel or sucking air. Easily 90% of the "lack of fuel" cases are due to a plugged filter. Had I known you had a fuel pressure gauge handy, my first response would have been "How's the fuel pressure when this happens?"

Begle1- I'm a big boy and can take care of myself.