HELLO, im trying to help out a family member with their Cherokee 4.0l auto( . IT HAS SAT FOR 3 YRS) we put in new batt, fresh fuel,injector cleaner changed fluids, plugs, wires, cap & rotor, fuel/air filt. got it to run (initially good) but now idles ok but stumbles a bit.
when we attempted a test drive it has no power stumbles badly hardly moves and dies.. any ideas ???

 

Could be dirt in the fuel lines, and even the tank. Even water in the tank from condensation. Try some dry gas. Also look for rodent damage. Wiring, vacuum lines, whatever. Remove and clean the engine grounds. Dont forget to check the tires if you havent already. Sitting for 3 years can be bad for them. Not just the outside, but between the treads, for any signs of cracking.

 

We have done all with the exception of the fuel dryer. even bypassed the fuel pump ballast resistor temporarily. but no luck

 

I'll bet the fuel pump is bad or the internal rubber hose inside the tank is wonky.