Phantom Phord problem

[stiles watson]

I accelerated rapidly to pass with my 6.4 L F350 (not towing). Shortly afterward, it was necessary to slow to 20 mph (speed zone). Then when I tried to accelerate back up to speed, it would hardly go. I figured it was one of three problems:

• Bad fuel
• failure of transmission to down shift
• Turbo failure

I traveled about 4 more miles to the rig, shut the engine down, and let it sit over night. Well, when I started it back up today, it runs fine, accelerates fine - no symptoms.

Have any 6.4 L owners experienced this kind of bog down? Have you had a phantom engine problem? With no symptoms, it seems useless to take it to the dealer.

[racerjoe]

sounds to me that the torque converter did not come out of lock up.It locks up at highway speeds to give you a 1 to 1 ratio (approx) and when you decelerate it is supposed to "unlock" so it will shift normal.

[KTManiac]

DPF regen maybe? ...or maybe variable vane problem in turbo ...or ECM error that reset itself? Who knows?!?! Maybe it went into "LIMP" mode and then re-set on re-start.

[noneck]

No MIL? Have you tried to check to see if any codes are pending?

[thor]

sounds like a dirty fuel filter staves for fuel when you step hard on it .let it sit and the fuel slowly fills the bowl

[8e3k0]

No codes came up? May of went to "limp mode" when it was accelerated and would not reset until you stopped and shut off engine. With no codes coming up all should be okay to go.

[stiles watson]

No codes displayed. In the 4 miles back to the site, it did gradually improve but not to normal. However, since restart, all has been normal including rapid acceleration and deceleration. I am due for fuel filter change in about 8000 miles. I guess I need to put it on the rack and check for water in the line.

[Jim Jarvis]

I've never had that problem Stiles.

[JimF]

Have heard of that one time, was a precursor to injector pump failure. Might not do it again for a year but when it does it is done.

[mlh]

Stiles
I had about the same problem with my 6.4. I was in the Shirley basin 5 miles from the nearest road 20 miles from a service station 80 miles north of Laramie WY, with my camper in tow. My truck would barley run. I was just hoping to get to the road , then to a service station to get some fuel. I made it. I cut my truck off to fuel up. I started it back up. It ran perfect, and has since then. Don't know what the problem was. No codes nothing.
You said it might be dirty fuel. Let me tell you this. I just got back from my dealer. They had the cab off a 6.4, dirty fuel. they were replacing the High pressure fuel pump all of the injectors and all of the fuel lines. Ford will NOT cover it, a ESP will NOT cover it. There went about $9000. Any time you think you have dirty fuel cut your truck off, and check. If you do have it toed to get it fixed. Water in the fuel will do the same thing and that too will not be covered by your warranty. If the low pressure pump goes out that will have the same affect but that will be covered, because that is not your fault.
Lynwood

[ols1932]

Although my truck is the 7.3L, it has given me the same symptoms. I've had it into the Ford garage twice here in Cedar Rapids, IA and there doesn't seem to be any consensus as to what the problem might be. My mechanic who has been working on these Ford diesel engines for 40+ years at the same location says that it IS NOT the fuel. He says he has seen some of these trucks where the fuel filter container was half full of water and the engine ran fine. He said it's not the turbo. I trust him because he's been the only one that gives me straight answers. We agreed that it is one of those mystifying things that may develop into something that will leave a code, and then again it might not. He advised me not to let anyone begin replacing a bunch of stuff to see if the problem will go away.

Orv