fuel pump not coming on five minutes later it might start like nothing was wrong week or 2 later it might happen again.im wondering about the security system playing a part in it, or possibly the key switch. i cut the truck off the other day and the fuel pump kept running until i turned the switch back on and off. i checked the relays , no problem.one time it would not start ,fuel pump would not come on, so i walked 100 yards to discount & got some wire to strait wire the fuel pump and when i got back to the truck it started right up like nothing ever happened. i dont think strait wiring would have worked because i dont think the injector pump had the signal to start?im lost and frustated!

 

Ok, number 1 - you need a fuel pressure guage. There is no discussion on that and no excuse not to have one. It can save you thousands of $ in injector pumps.

Scan the truck for codes.

This has nothing to do with the security system.

Have you swapped out your fuel pump relay?

 

i have replaced fuel pump relay, and i have an aftermarket fuel pump.when it happens it also affects the door locks.the first time it happened the headlights flashed on & off.

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just went out there turned key switch fuel pump come on & it started right up like nothing ever happened. please any ideas, a reliable cummins is now unreliable!

 

I think I would start by checking all the electrical grounds between the frame and body. I "think" there are 7 in total. Also the grounds around the engine as well as the power distribution box.

 

Swamprat did you ever figure out your electrical problem? I'm dealing with the same issues. I just replaced the VP44 and replaced the stock LP with an AirDog 100. I can't get the new LP to come on consistently. I'll be getting a fuel pressure gauge ASAP. In the meantime I need to get my fuel pump dependable. Do these lift pumps run full time? I don't have a problem wiring it to something that's on whenever the key is on.

 

Swamprat Does your truck have a remote starter? I spent a whole weekend with my dash apart just to find out it was the remote starter causing the problem.

 

I had to remove the alarm system on my truck for the same reasons! Mine was a Viper though, Ignition would do nothing... LP wouldnt come on and it was an intermittent problem.

Went under the dash and unplugged the alarm truck started right up. Plugged it back in a week later same problem. Its been disconnected about 4 months now no issues.

 

Thanks to all who have responded to my postings. I finally replaced my Crank PS and while I had my starter off I noticed I had a tooth missing from my gear that engages the flywheel. I also bought a new plunger and contacts for the solenoid. The activator wire broke way inside the solenoid where I couldn't solder it when I was taking the nut off so I wound up replacing the entire solenoid assembly also. I kept the new plunger and contacts for future use. Parts and labor to do the gear and solenoid, check my bearings and bench test - $90.00. Thank you Jim Watkins in Florala Al. If you're ever in that part of the world and need electrical work, he's the man! I installed the starter when I got home. The truck fired right up! I erased the codes and re-scanned PASS no codes! Went for a ride and she's back to blowin Black Smoke again and haulin ***. Hasn't been this strong in a loooong time!All I got left is to instal a FP Gauge and light, fix an oil leak at the Vacuum Pump and she's good to go! Thanks Again everybody!