I have a 2002 ram 2500, 2wd, quad cab, long bed, automatic, cummins. When on the highway at 65mph and cruise control engaged the truck will slightly accelerate then decelerate. it is weird. truck has 33000 miles on it and just start doing this. I am thinking it is the apps, but for 600 bucks I think I would like some other input before I peel open my wallet. I really notice it when I watch my fuel economy in the display. Any ideas?

 

By the way other than that problem it runs perfect. no hard starts, no accel problems. this just happens a steady speeds.

 

do you have a chip or programmer on it?

 

Nope. Bone stock. Think it might be related to fuel lift motor now. Didn't hear that usual oooomph when I turn the key on. I don't drive it much. Gonna order a lift pump and a tank fuel pump this week.

 

Get a draw straw and FASS or Airdog lift pump and quit worrying about it, and get better filtration too.

 

I ordered lift pump from Glacier Diesel. Saw It on the cummins forum. Had good reviews!

 

check your vacuum pump. also unplug your apps and plug it back in again. you also can try to reset your apps by turning your key on (don't start) and depress peddle slowly and release slowing three times and then turn key off and wait about 20 seconds before starting. got the last two suggestions from a shop foreman.

 

I actually found low fuel pressure from the lift pump. Going to put new lift pump, fuel pump, apps, low fuel pressure warning light. Then go ahead and put in a quadzilla w/pulseV2 and do 4 inch exhaust. Already have S&B cold air intake on. Cummins said if I had some return pressure then I might have gotten lucky and not damaged the injection pump. Although after I felt the truck acting funny I put in the garage and let it sit. So probably good there. Been wanting to do most of this anyway, just figure it is a good time to do it all at once!