I have 90k miles on my 04 CTD. Just lately I noticed an intermittent stumble when idling at stop lights. I changed out a very dirty fuel filter today and now I have a stalling problem sometimes at low rpm. I think the lift pump may have failed. I can still get the truck to run but I no longer hear the pump press up when I turn the ignition switch on.

 

AD150!!!!!!!!!!!!!!! In fact, they're on sale right now.

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