It has a fuel loss from time to time. it has a new fuel lift pump, fuel sending unit, fuel filter, fuel relay, the fuel filter housing has been cleaned. I took the line off the fuel out put of the lift pump and turned the key on & it sounded like it was sucking air, it had air in the filter cap also. What could be the problem?

 

sounds like you could have a rotted fuel line somewhere form the tank to the FFM. check good and heard for leaks all the way up there, and make sure the FFm isnt cracked

 

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