93 gmc jimmy 4.3 vortex fuel problem

[logden5751]

iv been trying to fix this for 3 months and can figure it out.I put a new fuel pump,sending unit ,gas tank,fuel regulater,and it still wont start .I get gas to the bleeder valve and if i spray either in the carb it will start.But quites when either runs out.

[rlith]

Originally Posted by logden5751

iv been trying to fix this for 3 months and can figure it out.I put a new fuel pump,sending unit ,gas tank,fuel regulater,and it still wont start .I get gas to the bleeder valve and if i spray either in the carb it will start.But quites when either runs out.

Ok, 1st off how did you confirm it was the fuel pump? Second, did you get the proper high pressure fuel pump?

Third, you don't have a carb, you have a CPI Injector assembly.

Have you tested the actual pressure at the shrader valve (just pressing on the valve to make sure gas is there doesn't cut it) Your pressure must be 56-60 psi to start the engine and 60-65 at running.

Have you checked your CPI unit?

Have you checked your Nut kit?

Have you pulled any of your spark plugs to see if they are full of gasoline? Check some of this, but check your fuel pressure 1st!

[logden5751]

the fuel pump wasnt kicking on so i changed it and it ran for a couple of days then it quite ..So i checked it again and the ground wire inside the tank on the sending unit was burnet so i just put on another tank, fuel pump ,and sending unit .It still didnt run.The pressure at the bleeder is 60 and a new cpi unit was just installed if that the box inside the moter with 6 wires coming off of it .Ill have them check the nut kit wheres that at .Thanks for the information.

[rlith]

The nut kit is the inbound/outbound lines in the upper plenum. If the driver's side intake is washed, you have a leaking nut kit which wuold give some of the symptoms you describe...

They aren't wires, they're tube (on the CPI) that's the fuel injector unit itself...When you put that in when you had the upper plenum off, did you have any washing?