Ok, in addition to the '96 1 ton with the bad turbo, and the '99 1 ton that sometimes goes to idle going down the road, now our '03 model 3500 cuts out at around 2250 RPM. A little background: In February, one weekend it got fairly cold here, (below freezing, but not arctic type cold), and I had the truck plugged in here at my house, but couldn't get it to start until the temp got above freezing again. Our mechanice thought the lift pump was getting weak, but after it warmed up some (the weather), it ran fine. Then in May, it quit (just driving along, pulling a trailer full of steers, and it quit graveyard dead), so they hauled it home, and after sitting a few days, it started. But didn't run right, so the mechanic installed a new lift pump. The pump that he replaced was in the tank, but the new one that was sold to us by the Dodge dealer was supposedly a "upgrade", that mounts in the engine compartment, somewhat similar to my '99 model. The truck then ran great until about June 15th, at which time it started cutting out at about 2250 RPM's.

At no load, (truck running in neutral), it'll rev up to red line no problem. But when driving, it'll run up to about 2250, then just fall on it's face, and if you keep your foot in it, it starts blowing out white smoke. I changed the fuel filter, with no effect. The mechanic hooked his Snap-On scanner up to it, and couldn't get any codes, and I've tried the ignition switch 3 time thing, and it just says "DONE", and then all dashes with no numbers. I'm wondering if since it's a different type of lift pump than came in it if maybe it's the lift pump, and just not giving a code?

It's an '03 4 door dually, 4 wheel drive, Cummins H.O., 6 speed with 112,000 miles on it.


Thanks.

 

my first thought was the fuel filter, but you changed that thing.

it sounds like you are still haveing a fueling problem. I would say your Crank Possition sensor is probably sending some funny info.

 

Well, I finally found the problem after about a week and a half of being mad all the time because of how it ran. It tried to suck the air filter thru the hose. The filter minder never moved a bit (must not work), and I never thought of it. It hadn't been long since the filter had been changed, but someone suggested looking at it, and sure enough it was all wadded up in the filter box.