I hope this does not show up twice. If so sorry.
I have a 1998.5 Dodge Cummins 24v extended cab long box. I use the truck to go get parts, pick up mowers, go to the store, and pull my car trailer with skid-steer on it. No extreme off-roading. The lift pump is located on the engine above the starter.
Last week on 12-8-13 I was bring my truck into the shop to put in a posi-lock cable system in the front diff. My truck stated to gel-up on the way into my shop, but it idled in. My shop is heat to about 65-70 degrease, it has been in there now for a week. I put the posi-lock in. Then went to change the fuel filter as I do about this time every year. I put the new filter in, filled the filter with #1. Bump the starter to have the lift pump kick in to help prime it. It ran for 1 second and quite, did not run for 20 seconds like it use to. I bought a new lift pump, tested it before putting it in and it also runs for only a second then stops. I have checked the wires going to the pump. When I hit the starter there is almost 11 volts, when the key is in the run position and the pump should be still running it drops to 8.66 volts. I have looked at the wires were I had to drill holes for the posi-lock and I did not hit any wires. It also has a edge d-541 programmer in it.
Thank you for you time.
Mark

 

i'm not familiar with that programmer, but set it to stock and unhook the programmer. See if this makes any difference. Check your connections also as you might not be getting a good connection.could the other pump have pushed gelled fuel up towards the injector pump and now the lift pump is just pushing against it so it builds pressure and shuts itself off?

 

Thanks for the reply. I have checked power and all grounds, also took programmer out. It has sat inside a heated shop for over a week, so there should no longer be and geld fuel. Also I have take the lines lose from the lift pump so it can not build pressure. Know tonight (12-18-13), I disconnected the battery's to see if it would clear anything. Hocked them up, bumped started it, and the pump ran a cycled like it should. So I hocked everything up bump started it to prime the system and know the pump will not shut off. Unplugged the pump so it would not drain my battery's. I am thinking It might be the computer?