Hard/No start after sitting

[CDegner]

I've had this happen twice now, both times after I haven't driven my truck for at least a couple days. The first time, I had not driven the truck for about 5 days. When I went to start it, it started up but it sounded like the injectors needed bleeding. It kept running and prmptly smooted out after about 15 seconds.



This morning, I went to go to work and the truck wouldn't start. I hadn't driven the truck all weekend. It turned over fine but it was not even trying to hit. Popped the hood, pumped the lift pump a few times and it started up but ran a little rough for the first 10-15 seconds.



I'm afreaid I know what it means but I'm hoping that others have had similiar experiences and it is cheap and easy... OK, at least cheap. Fuel filter has a few thousand miles on it. Is there any type of check valve in the injection pump that prevents bleedback?



Carl

 

[Greenleaf]

The lift pump is essentially the "check valve" for a lack of a better term.



GL

 

[JLEONARD]

Sounds like it could be the lift pump, but I would check the fuel system for a leak first.

You can put a few psi into the tank with an air hose... use a rag to "seal" it.

Jay

 

[cerberusiam]

I noticed the same problems developing over the last year or so. The lift pump was working but leaking a bit but as long as it was started every day or so no problems. A week sitting and it would take several 15 second cranks and a heater cycle or 2 to start. The truck sat for a week while I replaced the trans and the lift pump. Bleed the fuel system till I had fuel at the filter hit the key and ti fired right now. It definitely fires on the first cylinder up even after sitting over night in cool weather. Me thinks new lift pump is doing much better job now.



Now if the POD's get here soon I will see if the piston pump is up to the task.

 

[bgilbert]

I'm with Jay, sounds like an air leak between the LP and the tank. At 254k miles if all the fuel lines are original, there probly just about shot. I'd try to troubleshoot that first, that would be the cheapest. Then as far as lift pump goes, you can't go wrong with a low pressure piston lift pump. You'll get reliability and performance with it. I'm not sure what the stock 'Cummins' LP costs I think around $50-75, but a piston LP upgrade will cost you $200 for everything you need.

 

[guava]

Yep, what they said..

My 93 does the exact same thing. In my case its air coming into the system from at least two different places. I'm about to drop the tank and just replace worn parts (all lines) till I make the problem go away. Ugrading as I go of course.



I figure its just my trucks way of telling me to give it some attention. Mine has been doing the same thing all winter and it doesn't bother me enough to get out in the rain and fix it since the wife has currently occupied my garage space.

 

[BMote]

No Start

Definetly sounds like air/fuel mixture to me. Had same problem . I'd almost bet the farm that your fuel lines (either supply or return) are rusted out at rear of vehicle, probably right near the tank. Replace with new steel lines or just run new rubber lines from tank to bypass rusted lines... .

 

[desertrat1]

Mine did the same thing too. If I let it sit for awhile, it would start hard and run like crap for about a minute. The o-ring that seals the fuel pin in the AFC was leaking. Replacing it made the problem go away. Been fine ever since.