I have a 1986 5.0 that starts fine, but idles rough. I can drive her, but if I stomp the gas she will die. Acceleration is poor ( have to go easy on the pedal or she will bog down ) and mileage is horrible. Gave tune up, changed cap, plugs, wires; no difference. No cat converter, running cherry bombs. Can't find any vacuum issues. Totally lost at this point. HALP! Please!

 

It must be a bad vacuum leak somewhere or needs cleaning? or bad intake or carb gasket.

 

When I bought the truck and experienced the fuel problem I found the carburetor was loose on the manifold :/. Gasket was fine and I tightened it down. Cleaned the carburetor but no improvement. Will start following vacuum lines. Thanks for the advice, gave me a direction to follow!

 

Have you cleaned out the carbuerator? It's definitely worth getting that completely gone through. It almost sounds like a stuck float needle

 

Found a leaking vac line. Got the 4 barrel to kick in for the first time, but still coughs and sputters. Starts right up and idles fine, but I think a carb rebuild is needed. Am going to drive it a bit and hope for improvement. Hope springs eternal!

 

Taking the carb off, boiling it out and rebuilding it. $30 rebuild kit has everything and more. Taking over the kitchen table for a while

 

If this works, you better take your girl out for a nice night out. I mean your wife, not the truck.