Title says it all. My 1988 Super Duty has a low mileage wrecking yard engine in it with 40k miles. It starts and revs up just fine. Problem is that I am getting closer to 5 MPG and nowhere close to 10 MPG. It also is doggy without much spunk and the exhaust smells really rich. It stinks bad and the fumes will burn your eyes. The only mods I have made are to ditch the Cad converter, replace the single muffler with a huge free flowing one designed for a motorhome, advance the spark 2 degrees, and remove the venturi thingy in the plastic air intake that is right before the injector body. The truck has a manual 5 spd trans. What is wrong with this thing?
Dumpster
Dumpster