Flex fuel differences from normal

[Patrick Hammer]

I am installing a 1999 4.0l in a 2000 3.0l flex fuel Ranger. I know i have to change the fuel pump. I am wondering if there is any changes in the fuel lines. I notice the fuel lines run into a small device in the frame rail that is electrically connected. It’s not the in line filter… i dont see similar device on the 1999 4.0 donor…

This has been a bigger project than I anticipated. Changed our entire wiring bumper to bumper. Also replac dash. Threw away the troublesome pulse lock actuator. New suspension, motor, interior…
Front differential, brakes, leafs. Swapping entire wiring harness and dash is a challenge fraught with pitfalls… that combined with engine break has me taking it sloooow…

What’s the primary difference between Flex Fuel and normally gas fueled Ranger? Any thoughts?

 

[pjtoledo]

that gizmo on the fuel rail is the flex fuel alcohol content sensor. it tells the computer the percentage of alcohol
in the fuel.
when they fail they can flood the engine with massive amounts of fuel. also very expensive, over $600 !!!!!

other differences are stainless lines, basically stuff that won't be corroded by the alcohol.
if you swapped out the computer with a non-flex one it won't be looking for the alcohol info and the FF sensor
should not be needed.

since alcohol requires a larger quantity of fuel for the same power, the FF pump is capable of the increased flow.

 

[19Walt93]

There isn't flex fuel pump, when the sensor sees high alcohol content the PCM holds the injectors open longer to add fuel. We never had E85 here but we sold a bunch of flex fuel Rangers and Tauruses becuase that was the only way we could order 3.0 12 valves in them. When the flex fuel sensors failed the system defaulted to E85 mode and the engines ran pig rich. The price of the sensor really pissed off some customers, especially since we didn't have E85 available.