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Discussion Starter #1
Hey guys I have a lb7 and it has been dying while I’ll be driving it. It will start back up if I wait awhile. Brought it to two shops and they don’t know what’s wrong with it. Do you guys have any idea what I need to replace/ fix?
 

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Can you give some more information? To get it to restart. Do you have to pump up the primer? Do you have an aftermarket lift pump? Is it throwing any codes?
 

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Could be wiring to a crank or cam sensor, could be a bad sensor-if it loses cam or crank signal it will die. Could be bad ficm, could be a bad ignition switch, could be a fuel prime issue, could be a lot of things.... So its kinda hard to tell you how to fix it if you don't have more information than that
 

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Sucking Air?
 

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For it to start back up I’ll prime it and I’ll hold my foot on the pedal, but it won’t start up right away I’ll have to crank it for awhile. I do have a fass lift pump and no check engine light come on
 

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Fuel tank module. Had it happen on mine. Same symptoms. You’d have to drop the tank and from there it’s relatively easy. I seem to recall it’s a $300 part.
 

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For it to start back up I’ll prime it and I’ll hold my foot on the pedal, but it won’t start up right away I’ll have to crank it for awhile. I do have a fass lift pump and no check engine light come on
It will die when I come to a stop or slow down. It doesn’t throw any codes. Could this be a fuel pump issue?
Sounds like you need to be sure the lift pump is working and actually pumping fuel. When was the last time the filters were changed on the Fass?
 

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Is the problem more likely to occur when the fuel level is below some specific point? More likely when front of truck is lower than rear or vice versa? Every try removing or loosening your fuel cap to see if it makes a difference?
 

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Are you running a sump or pulling fuel from a straw? Sounds like your straw is sucking in air and killing the truck, get a sump.
 
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