If your Dodge diesel runs rough at 2100 RPM it is probably starved for fuel. Have the fuels filters changed and / look for an air leak in the fuel system. My 1996 had rusted fuel lines on the top of the fuel tank. cost about $600. Canadian to repair.
Try checking for the crankshaft sensor
Yes. the computer runs the cruise.
It is built into the liquid line that runs along the passenger side fender.
temp senser or spark coil
It is the same fuse that feeds the PCM. So if the truck runs and the alternator works it is not a fuse.
sounds like an injector is bad.
try checking out the coil pack
Depending on how far off, runs rough, check engine light, no start, engine damage.........
You dont you replace the timing control module
i have a 3406b inframed new head injectors runs rough and pours white smoke had pump and timeing advance off timeing advance rebuilt put back on. now its worse
dodge is known for fuel pick up issues. the fuel sender unit has low voltage. change that and fuel filter. nnot an easy fix . because both are in fuel tank.
it runs a little rough at first!