Engine Stumble

[SRehberg]

Recently our son purchased a '03 2500 automatic 4x4. It now has about 105,000 miles on it. The other day he accelerated quickly which produced some but not a lot of black smoke, but the engine started running rough like it dropped a cylinder. Pulling over the engine idled but rough, so he shut it down for about 30 secs and restarted. All was well again but he hasn't tried accelerating hard since. The truck is bone stock and as a 12 valve owner I am at a loss where to begin with all the electronic controls. I read the threads and injectors seem to be a common weak area but do they work intermittently? Thanks for any guidance.

 

[JJPage]

You stated it is stock... has the factory lift pump been replaced? If not, it is due. The factory pump is located on the back of the fuel filter canister, the easy fix is to buy a replacement pump from Geno's. If the pump is not present on the fuel filter canister, someone may have already replaced it with an in tank version or a frame mounted pump.



If the pump is failing, it could cause the symptoms you described.



Check for codes by turning the key on and off 3 times(without starting), on the 3rd time leave in the on position, any codes will show up in the odometer window, if none, or when through, it will say "done". The P code reference list can be found under the "5. 9 engine and transmission forum".



Jess

 

[SRehberg]

Jess thanks for the reply. The lift pump is original as far as I know (not in the tank) as it was bought used with 87K on the odometer. It sure would be a lot better to replace it than having to buy injectors! We'll check for codes as well and see if that gives some direction. The Check Engine Light never came on. Thanks again.

 

[JJPage]

The lift pump could be at a condition where it runs, but not keep up with the CP3 injection pump at full throttle. Sometimes the lift pump can fail with no codes, and you can have codes with no CEL... electronics.



At 100+k miles the lift pump is going to be close to failing, dealer no longer has them, that's why I recommended Geno's, they have a direct replacement.



The injectors weak spot, is their filtration, the factory 10mic is not sufficient, you need a 2mic aftermarket filter before the injection pump. Also at the mileage of your sons truck, the injector cross tubes should be retorqued to 37 ft lbs, this can be done by yourself, and could also be contributing to the current symptoms. The cross tubes loosen over time, causing leaks and loss of rail pressure, the fuel leaks back through a passage in the head to the return line at the back of the head, it's not visible so you cannot see it. An injector return fuel test can verify, but simply retorqing just eliminates the possibility.



I would do these steps before replacing or suspecting injectors, both are simple, the lift pump($179. 00@Genos), and retorquing free, if you are somewhat mechanical.



Let us know what you find out, codes, etc.

 

[SRehberg]

Thanks Jess! We'll definitely check the items you suggested and let you know how it goes. We'll check with Cummins about a better filter or else we'll need to look at a good aftermarket filtration system to keep this truck as healthy as possible. Thanks!

 

[BLoging]

if it is the lift pump, it will keep doing that ever so ofen and it will take out the the cp3 pump if not taken car of. when it dose that it is not getting the fuel psi that it need's and is trying to get the fuel from the tank. He sould notce his fuel economy is down too!!!

You all so can look a at a Fass fuel pump with filter's, the platinum come's with a donaldson that i thingk is a 2micron filter.
Ijust put a fass platunum on my 2004 dodge ram 2500 with 63,000 on the clock, got fed up with the dealer repaceing the pump about evey 11. 5 mounth's. the fass pump has a littil pump noise, the fass platuinum has 2 model's a 90 and 150gph i have the 150 and like it alot. the cost for the fass was about a littel less than $500. 00 and i put it in my self in about a day( after getting the bed off of the truck). the web site for fass is fassride.com. I think that pump is avalible on genosgarage.com like what was posted above by other member's

 

[SRehberg]

Thanks for the reply. He's looking at the FASS double filter system to replace the stock lift pump; a bit pricey but definitely cheaper than a CP3 pump or injectors. We scanned the truck for codes with a OBDII reader and nothing was stored. We will let you know what we find but it maybe a bit until the FASS arrives and gets installed. Thanks for the help!

 

[JJPage]

Here's a good link with photos, done up by our fellow TDR member sag2. It will assist you in torqing your cross tubes.

https://www.turbodieselregister.com...148621-injector-install-procedure-photos.html



I believe the FASS is a great idea, kill two birds with one stone, so to speak.



Jess

 

[SRehberg]

Thanks for the link!