We own a 99 HR Endeavor with the 5.9 Cummins.Last year after returning from a 4 month winter trip we wanted some maintenance done. My mechanic called me and told me he had trouble starting the MH. He determined it was the electric fuel pump and replaced it. We went on our 14-15 winter trip and had no problems.In spring we wanted annual maintenance. My mechanic informed me he had the same problem again (starts runs for 3-5 seconds and dies) and replaced the pump again. It happened to him yet again and this time he installed an OEM pump. I brought the coach home. Tried to start it a couple of weeks later and it happened yet again. This time he thought it was sucking air somewhere in the line from the tank to the pump. He tightened everything and it started. He called me last Wednesday and said it was all set. They had checked it at least 15 times and it started. We went to pick it up Friday AM and same thing happened.Any of you wise people have any ideas?

retiredtravelers2013 wrote:We own a 99 HR Endeavor with the 5.9 Cummins.Last year after returning from a 4 month winter trip we wanted some maintenance done. My mechanic called me and told me he had trouble starting the MH. He determined it was the electric fuel pump and replaced it. We went on our 14-15 winter trip and had no problems.In spring we wanted annual maintenance. My mechanic informed me he had the same problem again (starts runs for 3-5 seconds and dies) and replaced the pump again. It happened to him yet again and this time he installed an OEM pump. I brought the coach home. Tried to start it a couple of weeks later and it happened yet again. This time he thought it was sucking air somewhere in the line from the tank to the pump. He tightened everything and it started. He called me last Wednesday and said it was all set. They had checked it at least 15 times and it started. We went to pick it up Friday AM and same thing happened.Any of you wise people have any ideas?Look for a bad GROUND wire - either the direct or a secondary to the Battery - if he still has the old pump do like most mechanics do, "Check it out on the bench to see if it is truly the Problem" if it works on the bench then likely the ground.Over the years the grounds become an issue, on many occasions.JMHO,

I have the same year endeavor with the 5.9 cummins. Recently mine started acting up as well. Doesn't want to start. You can crank and crank, never starts. If you bump the starter that should get the fuel pump turned on and pressure built so you can start it. If your pump is not putting out the pressure it should, it may take several tries before it starts. That's what mine is doing. I don't know if mine has the original lift pump, but the previous owner already had a lift pump die and take out the very expensive VP44 pump. I am going to upgrade my lift pump to something from FASS when I have a few extra dollars. From all the reading I have done, the factory lift pumps are not that great.

Thank you for the tip regarding the ground.And to Glamisorbust. My mechanic told me at least two of the times he tapped the pump and it worked. Does not make sense that it does not have enough pressure to start but enough to run at 70-75. Does anyone have any logic? I have looked at the FASS, but they are pricy indeed.

Have him look for an air leak past the lift pump. On the fuel rail assembly. You get a tiny leak there, and you get those symptoms. A leaking banjo bolt will cause that.If he's tapping the pump and it starts right up, but he's replaced it already, I think that just might be a coincidence, or maybe the tap is vibrating up to something else.I feel for you and your mechanic though. Tracking down an intermittant problem is the worst.

Don't know about the 5.9 but most deisel engines also have a fuel shut off solenoid in the injector pump circuit. If the spring gets weak in these they will intermittently fail causing the engine to run a brief time then stall.

5.9 Cummins fuel problem (Still) | Good Sam Community

jurzbill
Explorer
Sep 20, 2015
I had the same problem. Took it to cummins and had checked. it was a fuel leak. they repaired and no problem since.
retiredtraveler
Explorer
Sep 18, 2015
So the update is that there is no update. After yet another couple of weeks my mechanic swears he has checked the entire fuel system and found nothing wrong. He has started it 12-15 times the last 3 days and it starts and runs fine. I explained we are very concerned about going on a multi thousand mile trip not knowing the problem. He understood, he camps in a class A himself. He said he does not have the software to download the trouble codes. So I called Cummins who referred me to an authorized Cummins dealer here in CT. So we pick up the MH tomorrow (If it starts) and off to Cummins service center Monday. Stay tuned.
Passin_Thru
Explorer
Sep 13, 2015
Why aren't they testing fuel pressure while starting? Next, they need to blow out the fuel lines, sounds like something caught in the line maybe in the fuel tank. Could be leaking at the filter and getting air in it thus never getting fuel to injectors.
hooligan
Explorer
Sep 12, 2015
Normally the fuel is pulled from the tank by the lift pump, then goes through the fuel filter on it's way to the injection pump.
Air in the filter would indicate a leak at or prior to the pump. (Fuel lines, fittings or gasket.) A leak after the pump would also leak fuel because those lines are pressurized.
Air in the filter after it is sealed is pushed out by bumping the lift pump several times. Your indication of engine running for a short time then quitting shows there is air in the filter. Air may have to be bled at the injectors to clear the lines after the injector pump.

Cummins later moved the 'lift' pump to the tank so that it pushes fuel rather than sucking, which is more efficient.
retiredtraveler
Explorer
Sep 11, 2015
Sorry, not a couch problem,, LOL
retiredtraveler
Explorer
Sep 11, 2015
This is a Freightliner chassis. Since the couch is at the repair shop I can't go check myself hence the question.
Jim
Explorer
Sep 11, 2015
Just remembered...had a very similar symptom show up just a couple months ago. I'd filled the tank with diesel, drove home, then drained the water from the fuel filter.

Next morning, started right up, but died 30 seconds later.

Turned out I hadn't tightened the drain screw tight enough. Allowing air to be sucked into the fuel line.

Maybe check or just replace the water separator?
wolfe10
Explorer
Sep 11, 2015
Your chassis maker designs and installs the fuel filter(s).

So, check with them.

Could be just one (usually on suction side of lift pump). Could be two, one on each side of the lift pump. Suction side= between fuel tank and lift pump.

If Freightliner with the B motor, I vaguely remember that there is also an in-line filter on the frame rail.
retiredtraveler
Explorer
Sep 11, 2015
And the problem is? Still no clue. My mechanic told me this AM that this engine has an internal electronically controlled shut off. He did however tell me that when he bleeds the fuel filter it has air in it. After he bleeds it the engine starts. Is the filter before the lift pump or between the 2 pumps? Does anyone know. That could be a clue.
Busskipper
Explorer
Sep 09, 2015
retiredtravelers2013 wrote:
Thank you to everyone for all the suggestions. I will make a list for my mechanic and present it tomorrow.

And the problem was?

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5.9 Cummins fuel problem (Still)

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