I have a 1998 JGC 4.0 6Cyl. 129k. I had to replace the sending unit in the gas tank which went fine and fixed the fuel guage! But, a few days after that another problem started. when I start the jeep and start driving it is like it starts starving for gas it jumps and sputters and stalls, but if I hold it to the floor it smooths out and runs fine until I let off the Gas and it starts again and this will persist for 1-3 mins and then it smooths out and will run fine as long as I want to drive it, even when I park it for a few min. it runs fine but if I let it sit for 30-1hr. it will do it again! I have replaced the TPS and cleaned the Trottle body as clean as I could get it! I have run all kinds of fuel additives through it with no improvement! I have tried everything I know to do and nothing seems to help! Please throw me a bone. Thanks, Chad

check your fuel pressure. See if its related to the fuel tank r&r