help, truck runs like no fuel pressure?

[dmaxx3500]

guys for the 2nd time in the last month,it looks like i need an other fuel filter,before that i went 1 year, the year old one i cut apart and it was black thru out, the 2nd one was black 50%,im going to change this one tomorow morning,and i will cut this one open too, could this be something other then ''dirty fuel'',,like a bad fuel pressure regulater?,,,, ck eng lite comes on at 60-65mph on the cruise control and going up a small hill,then no power and eng can't run over 1800rpm's,after sitting at walmart for 1/2hr it ran fine but less power and in the dark it could fog for bugs in following cars headlites,and milage went from 15 to 9.6 on the dic,,so it must be running the inj's wide open,,eng code is low rail pressure,both times,lite goes out 3-5 key cycles and code is in history,,this happened in des moines today then i tryed to buy a filter at a parts store and nobody was open ,so i drove it 175 miles back to dubuque to customers shop,,any thoughts?

 

[saratoga]

What are the code(s)?

Is it a P1093?
IIRC, some others that have had this problem kept setting that code when having rail pressure issues not related to the fuel filter.

 

[dmaxx3500]

yep thats the code,i just got back from a trip 500 miles and still less power then before,90% of the way back,i took out the air filter,truck seems to have more power,im going to use the tech2 tomorow to ck the egr

 

[dmaxx3500]

just did it again , code is p0087,low fuel pressure,,everytime you push the gas pedal to leave a light you get black smoke,anybody know what the fuel pressures are at idle,1000,1500,2000,2500,3000 rpms,could this be a bad pressure regulater?,or inj pump?,