Engine is loping bad

[Soot_Life]

So I switched IDM's and got my truck running finally.. overall I have switched the speed sensor, mech fuel pump, cps, and idm.. hpop is good fuel pressure at the regulator is good. full tank of gas and all..

the truck ran fine for two days and then it started acting like it was out of feul... ran through everything again. changed the oil even(in a desperate attempt) im at my witts end.. im thinking maybe I got two bad cps's??

sometimes it runs fine other times not so much.. my tachometer is all over the place.. tried unhooking my alternator in case it was spiking.. no change there... any chance it could be something other than the cps?

[madpogue]

Brand and source of the new CPS?

(Full tank of gas could be a very bad thing.... )