I am working on a 98' Dodge 3500 standard cab 4x4 auto, turn on the key, cranks but won't start, checked out and found power to the lift pump, pump not workin, changed out pump, turned on key and it comes on and starts, though problem fixed, shut off, went to restart, but wont. turn key off, then back on, took about 30 sec, pump came on, cranked over and started right up. if you turn the key on, no lift pump, bump the starter, no lift pump, it comes on when it wants to. checked connections, all ok. if the lift pump does not turn on, the truck will not start. Any idea's? The only after market thing on the truck is a VanAken Box unit. might add that it's a 24v

 

Um? No one Has seen of this strange phenomenon?

 

to my knowledge the ecm controls power to the lift pump , try taking the power supplied by the normal plug in and use a constant 12 v source on a switch, that should tell if the ecm is causing the problem turn the pump on to get fuel pump flowing and try starting the truck. also check for codes if you have a scan tool that is the best way, good luck hope you get it figured out, will talk to couple of other friends and pick their dimented minds and will post back