SilverSootXpres

Alright, I've had nothing but a headache with a problem I've had since about October 2006.

I was driving steadyat 60mph, let off the throttle and coasted down to about 40mph, when I pushed the clutch in to downshift to 5th gear, and it died. Just like someone turned the key off. Wasn't able to start it. Would turn over fine, but that's all it would do, is turn over.

Hauled over to the diesel repair shop that night on a Saturday. Monday morning comes, he goes out and it wasn't throwing any codes. Pulled it into the shop, cracked 3 lines after the VP-44, and after a few seconds, it spit and sputtered fuel out and then started. Tightened the lines, test drove it for awhile. All good. A week later I started to notice a "Bucking" like a fuel miss when I'd moderatley (20-28psi) accelerate in 6th gear. Tested numerous things on it, no codes were being thrown still, but the Dodge dealer figured it was the VP-44. Since it was under warranty, I wasnt' going to argue fo a new VP-44 at 75,000 miles.

The truck still bucked after the new VP-44, but was driveable, and hadn't shut off on me after that. We were still trying to figure out what the bucking was. I also noticed a dead pedal issue when coasting for a considerable distance and the stepping on the pedal. When it would do that, it wouldn't shut off, just drop to idle. Then a second or third tap, it would come back on again. Wide open throttle it performs flawlessly.
This past weekend I drove it to Minneapolis to visit family for Easter, and I had driven 180 miles, got off the highway to get onto another one, and when I was coasting to a stop light it shut off on me again. Tried cracking the lines and that didn't work for me. No codes again. Same thing what happened in October. Got towed to a large Dodge dealer. Monday morning the tech looked at it. He cracked the lines after checking for codes and it sputtered for a few seconds and started back up. I ran it back home 180 miles again and it didn't die. Still bucks though. 3 techs with combined 50 years of experience on CTD's haven't been able to find any leaks in teh fuel system.

Here's what has been replaced since December and hasn't corrected any of my problems:

VP-44, TPPS, Map sensor, Cam sensor, 4 injection lines, all injectors tested.

Also had the edge comp out and it still does it. It does effect how hard it bucks, but it's believed to be exaggerating the problem with more fueling.

Sorry for the novel. I'm just baffled nobody is able to fix it.

j-fox

WHAT is the fuel pressure? Sounds like it is at ZERO!

Twodiesels

I feel your pain! I have nothing but trouble with my Dodge/Cummins.
It is the most unreliable truck I have ever owned.Good luck!

SilverSootXpres

Fuel pressure is 15-16psi. The lowest I can get it to go at WOT is about 10-11psi.

About the only logical I'm going to try next is an ECM. I replaced that once back in 12-04 already, but I don't know what else it can be at this point. Hopefully the 7yr/100,000 warranty covers that. They don't exactly sell those at the dollar store. Looks like $1000-1200 from what I found.

Dear lord please be warranted, that's my turbo fund money!

fredbert

It sounds like air is getting into the system somewhere between the fuel tank and lift pump. That's the suction side of the system, so air will leak in, not fuel out. And as I recall, this is fairly common on 2nd gen trucks. Hopefully it's something as simple as that. At least you got the VP44 taken care of free of charge!

rattlerbob5.9

Silversootxpress
Sounds like an intermittant electrical problem or like you said possibly the ECM at this point i would be very carefully checking and cleaning all grounds first and then all plug in connectors and the pins inside them. Since you are in the rust belt/salt district you might want to add some dielectric grease to the connetors.

H2SRDMB

how about the tps.. have you tried a reset for it... i know i was getting weird stuff happening, untill it went wide open on me at a trafic light.then it was dead period. and when it would act up. shutting it down would fix it temporarily. sometimes not. i did have some not so easy starts. but nothing a second try wouldnt do.

maybe yours is doing the same but on a larger scale!

my 2 cents worth!

badme

Check and clean the grounds. It is fairly easy and cheap. To much voltage drop will do a lot of weird stuff.

masterphreak

I would have to agree that it is most likely a leak somewhere in between the tank and the pump. Try and reaplce all the fuel lines from the tank to the fuel canister.

SilverSootXpres

Today I went through all the fuel lines, found some seapage on 3 injector lines. Replaced those. Still bucked in 6th gear between 18-22psi of boost.
The automatic shut down relay was throwing a code. Put a new relay in. Drove it for 30 minutes. Still bucked.
When I'm rolling 6th gear at 1500rpms and mash it to the floor board, it doesn't buck though. Not sure why it will only buck at moderate throttle acceleration.
I'm still learning parts and stuff on here. Anyone know of something called a a"co-pilot" for diagnosing the computer system on the ECM & PCM?
Cummins Npower out of Weston is borrowing a unit to my Dodge dealer that as far as I understand it, gets hooked up to the truck somewhere and then they take it for a drive. Once they get back with they can view graphs of everything on the truck of what it's doing. They seem to think it's an ECM problem. I was also told the ECM is covered to 100,000miles, so hopefully that's the problem.
Of course I haven't been able to get it to shut off on me again.
These intermittent problems sure are tough to diagnose.
Looks like Monday we'll try that stuff.

SilverSootXpres

Do you mean the trick with taking the battery cables off for 30min-1hr, then reseting the pedal? If so, I did do that. Along with an entire new APPS. No dice.
Thanks.

SBishop

What was the fuel level when you have the problems?
Somewhere in the far recesses of my dim memory I remember reading about the fuel line in the tank rubbing against a screw and getting a hole in it and at lower fuel levels sucking air into the system.

PaulDaisy

+1 for air leak on the suction side.
There is a simple test: install a piece of clear line (teflon or nylon) before the IP or fuel filter and watch for air.
-P

H2SRDMB

crap i was just thinking that too. great idea on the clear tube..

good luck keep us posted

badme

Check out this post
https://www.dieseltruckresource.com/...d.php?t=139601