Intermittent light surge at hiway speeds.

[JReichenbach]

Hey all, my 2005 3500 Dually sometimes has a slight surge at 65 to 70 mph, when not towing my cars around. Truck has had updated injectors, Banks intercooler and air Intake horn, and an older Edge box that runs in Tow mode. Truck has trailer hooked up 95% of the time, so i havent been to concerned about it. My son was up for a race last summer, and commented on it, he had noticed it when we were down south at a race earlier in the year.
It is very subtle, sometimes you dont feel it, then it just shows up. Ive tried Tow/Haul modes, no effect, does it with or without cruise on. Havent tried unhooking Edge box yet. Could it possibly be the potentiometer in the gas pedal, or maybe some sort of fueling issue? Any other possibilities that I should look into. Truck pulls great, and Mileage, since I upgraded to the 2 car trailer, hasnt hardly changed. Thanks for help. Jim

 

[AH64ID]

I have seen larger injectors cause a surge, but only with cruise control engaged. It’s easy to tune around, but it’s certainly a thing.

None of that has been with an Edge thou, maybe it will do it out of CC. I would disconnect the Edge and see if it goes away… then I probably wouldn’t hook it back up as they aren’t a great option on CR’s.

 

[JohncJordanIII]

Hey all, my 2005 3500 Dually sometimes has a slight surge at 65 to 70 mph, when not towing my cars around. Truck has had updated injectors, Banks intercooler and air Intake horn, and an older Edge box that runs in Tow mode. Truck has trailer hooked up 95% of the time, so i havent been to concerned about it. My son was up for a race last summer, and commented on it, he had noticed it when we were down south at a race earlier in the year.
It is very subtle, sometimes you dont feel it, then it just shows up. Ive tried Tow/Haul modes, no effect, does it with or without cruise on. Havent tried unhooking Edge box yet. Could it possibly be the potentiometer in the gas pedal, or maybe some sort of fueling issue? Any other possibilities that I should look into. Truck pulls great, and Mileage, since I upgraded to the 2 car trailer, hasnt hardly changed. Thanks for help. Jim

sometimes they are a pain in the butt due to dirt and corrosion but changing the FCA (fuel control actuator) can help. They are a common wear item that will cause surges. Located bottom left on back of CP3 pump they are torx bits so make sure they are clean before attempting

 

[JReichenbach]

I do have a spare FCA in truck, I'll give that a try. AH641D, why do you say that about the Edge, curious to hear what you know. Mine is an older one and was contemplating upgrading to one of their newer units. Thanks for insight. Jim

 

[AH64ID]

I do have a spare FCA in truck, I'll give that a try. AH641D, why do you say that about the Edge, curious to hear what you know. Mine is an older one and was contemplating upgrading to one of their newer units. Thanks for insight. Jim

They run more rail pressure and hotter than needed for the power they provide.

 

[JReichenbach]

Good to know, does that apply to the newer ones as well?

 

[AH64ID]

Good to know, does that apply to the newer ones as well?

As far as I know, but haven’t looked into much in a while for the 5.9. I also don’t think they have updated them recently, just new software platforms.

 

[CBari]

Have an 03 that developed the same symptoms. It also had an edge on it that had been there for years with no problem. Seems that the wiring on my edge was the problem took it off and the problem went away. I say wiring as mine was the juice model and had several points that it interfaced and I could turn the unit off and back to stock and the problem was still there but as I would disconnect various connections the problem would go away. I removed the edge as I was no longer using it anyway.