I have recently replaced lift pump, tank & SENDING UNIT, bled the fuel line & it ran for a while, but stalled at stop, ps truck hasn't been used much in a year, I filled up truck & added fuel ADDITIVE FPPF, I gave it 1/3 of a bottle for 1 full tank, truck smokes & stalls, has new pmd, what could possibly be wrong? I got it home after topping off fuel to make additive not so rich & let it iddle, it ran fine, it was running erratic in park with accelerator pressed down, but stopped doing that once at home. Thanks for any help guy's!

 

Since you just replaced the lift pump ( I also did that in my 84 6.2 yesterday, actually) i think it may be your switch between the 2 tanks. I have read that that can cause alot of stalling problems in these trucks. it may also be the injector pump. I'm sorry if im way off, but it may be something to look into.

 

i woild also do ops check or replace it

 

It turned out to be the chip in the pmd, aftermaket...