92 S10 Blazer 4.3 mpi bad hesitation
 

Hi everyone. When I run it, after it is warmed up it has a bad hesitation just sitting in park. It sits there and bogs for a while and then it will die if I don't let off the accelerator. If I pump it a few times it will rev up, but if I try to just step on the fuel a little bit, like to 15000 rpm it will bog real bad. It will also just die out of the clear blue, but will start right back up without ever turning off and on the key. I have done a complete tune up and a new fuel regulator and a new fuel filter. The thing sat for like a year or so because the shop couldn't figure it out. I put new fuel in it. They said they put a new fuel pump in it. I am not so sure because the fuel Gage (electronic dash) goes all over the place. Sometimes it shows full and others it shows a quarter. That is without adding gas. I has no codes. I checked for vacuum leaks and have found none. I have a snap on mt 2500 scanner, and have checked it. The thing that bothers me is that when scrolling through the mt 2500, the fuel pump voltage is between 10.5 and 11.1 volts. I am thinking that it should have at least 12 volts to operate correctly. Any suggestions would be greatly appreciated. Thank you in advance for any help.