1988 not running right

[scrappyk5]

i had a problem at the beginning of the year where it seemed as either it wasnt getting enough gas or i had water in the fuel. what happens is the truck will idle but a little rough. it will go with giving it some gas but then it acts like its not getting any gas , so i press on the pedal and nothing happens untill i press it about 3/4 , then she will bolt like a bat outa hell. now as long as i am holding about 3.4 pedal , she will just keep building speed. then when i get to the speed i want , i let off on the pedal and she acts like she loses all power till i press hard on the gas again. its like the gas is not working till i am pressing almost all the way down. i dropped it off at the dealership and they said it wasnt throwing any codes. they also thought there was water in the gas. so they kept putting dry gas in it. well she seemed to get better. well the truck wasnt used that much , mainly for a trip to the store here and there untill a month ago. i started driving it to work , and she ran great like she is normal. but this morning it started doin it again. could it be water in the gas , or am i having a problem with the pressure regulator ? or what ?
like i said , she idles and will drive, but if i give it a little pedal , she will buck the a bronco , untill i practically floor it , then she will bolt like she should. now once i get to the speed i want and i let off on the pedal , she seems to lose all momentum , then i will start slowly pressing on the pedal and nothing happens till i get about 3/4 , then she takes off again.

also , with it running , i can rev it up as if there are no problems

 

[kram]

rough idle and stumble

hey how ya doing.
my 88 gmc suburban has the same problem.
seems like it always did (4 years).
just finished a total rebuild and the symptom got worse.
went through every trouble chart in the book.
check the pick up coil and rotor.if the magnet is swollen replace it.
there should be a solid click to the shaft when rotated by hand.
i replaced the whole dist. $80.00 at advanced auto (in stock).
90% cured.also recheck the egr vac.. mine seems to have
partial vac at idle.if i unplug the line and test drive.
the stumble goes away.maybe a bad vac soleniod????


let us know. kram

 

[scrappyk5]

well to update my problem , i drove it home yesturday and it drove normal.
no problems. then i got up this morning to drive to work , and it did it again.
so is this a morning problem