What type of fuel system does a 99 F-150 w/ 5.4 have? Is it returnless or return style?

 

Manual shows a return system.

Inspect your rail and see if it has one (returnless) or two (return) fuel line connectors.

Steve

 

it is a return type, the new body style F-150 have returnless

 

sorry for the noob question, but what does the return accomplish?

 

the fuel line is kept at presure and the fuel not used by the injectors returns to the tank, in the reurnless it does not

 

Fuel pressure is maintained by bleeding off the excess pressure back to the gas tank using a regulator valve and a return line. A returnless system varries the voltage to the fuel pump to control fuel pressure without returning fuel to the tank.


JMC

 

YOu're better off with the return system. It provides as much fuel as needed and expels unused back to the tank. Lots of Mustang horsepower finatics spend a couple grand converting their returnless into a return system. THere was a big article in Muscle Mustang and Fast Fords about a year ago about the returnless system.

 

thanks for explaining that