Hey everyone, I was wondering if someone could maybe give me an idea of what is going on with my truck. I have a '73 F-100 with a carbureted 302 swapped from a '92 F-150. The truck recently started spitting and sputtering after it gets warmed up and while you're pressing the gas, so I changed the fuel pump. It's improved some, but not a lot. When it gets to running temperature and stays for a while, it starts cutting in and out, acting like it's gonna die, then when I let off the gas, it'll idle and sometimes the issue stops, sometimes keep going and sometimes dies. My fuel line lays directly on the motor all the way from the fuel pump to the carb. A buddy of mine said it may be vapor locking. Anybody else had this issue before? Any advice is greatly appreciated.

 

Whether or not the fuel line is the culprit, that has to be fixed right away. You can't diagnose an engine with something that egregious going on; it adds too many variables. Route the fuel line properly, and then see where you're at.

Not sure how you found a carbureted 302 in a '92. That means the motor was swapped IN to that truck in the first place.

 

Whoever had the truck first, redone it a little to keep it "original" by making it carbureted and not injected. It's definitely got me a little gun shy of it cause I'm tired of sitting on the side of the road

 

Have you checked your timing?
-plugs and wires, cap and rotor
-cleaned the carburetor
-fuel filter