I have a 2003 cummins that runs fine it just cuts out or looses power goin down the road at random, it doesnt matter if its cold or if its hot, if Im accelerating or crusing. After cutting out for a few seconds(5-10 seconds) it picks back up and runs fine. Just every now and then it cuts out when accelerating other times it does it with the cruise set. There is no given reason. It doesnt even do it every day. Ther is no proble starting truck except one time my fuel canister was empty(before I changed my filter and pump in the tank). It seems to happen more often when I accelerate. It does not cut out at the same time or same application and my engine light comes on. I have changed the fuel filter and fuel pump in the tank. I did the simple codes check with the ignition switch and the code 2120 & 2121 came up so i changed the throttle position sensor which is what the code was and it still seems to act up on me. since changing the filter, fuel pump and throttle position sensor I have not been able to see if my canister has been empty again because it picks back up and by the time i get stopped to look its full. I have no fuel leaks or lack of power issues(except when its cutting out). Any help or a possible diagnosis for this would be greatly appreciated as I am out of work right now and cant afford the expensive dealership engine scan. Thanks for any tip or help I can get.

 

Without undoing the batteries, key off, unplug the TPS, wait a few seconds, then plug back in. Turn key ON, do not start, then slowly press the accelerator to the floor, then slowly let up. Turn key OFF. Repeat key on/off pedal thing two more times. Then drive.
Or maybe you're sucking air into the fuel system.