Dodge Repair: driveability degrades but no codes


Question
i have a 07 3500 with a 5.7 hemi 65000 miles, having a problem with skipping, was having lean bank 1& 2 code, replaced crank& cam sensor's reset comp. took care of codes & a surge prob veh was having. not skipping probem at 4200 + rpm fuel pressure is holding steady at 51/52 psi. seems the more i drive it the worse it seems to get, if i disconnect batt & clear comp codes(hod neg,poss terminals together)it runs perfectly(engine)goes rite to 5500 with no issue's, at that point it dosn't seem to want to shift up, but skip is gone... if u let off throttle veh will shift up. seems to run fine for acouple day's progressively getting worse,seems skip starts around 4500, & keeps dropping lower &lower, ie 4250,4000, etc.  note, original problem was a fuel pump(died) replaced it less then 1 month ago... fuel pressure gauge dropps to 45 after sitting(off) for 10/15 min. i believe i have abad comp! i have no codes showing up, fuel pressure is stable(51psi)from 750-4500 . even when it's "breaking up",skiping fuel press is still at 51...not sure where to goto next..?

Answer
Hi Dan,
With no codes you are unfortunately having to guess for what might be wrong. You could wait a bit more until a fresh code appears is one approach.
While you have been focusing on the fuel supply, the other side of that equation is the mixture being too lean due to some sort of a vacuum leak into the intake manifold or some other way the mixture is progressively being leaned out as the cause.
Checking the vacuum hoses for loose fittings or cracks is one idea. Also check the crank case ventilation hoses. Finally consider whether the egr valve might be gummed up enough that the valve is sticking slightly ajar when it is supposed to e closed tightly which also leans the mixture which shows up either when accelerating or slowing to an idle as missing. You could remove the egr and check out the valve interior condition fairly easily on the 5.7L engine.
Roland