To give you some background, I have a 2003 3500 with a 5.9/6 speed. About a month ago, I believed my factory lift pump, no big deal. I installed a FASS pump in hope of fixing the problem. Well it didn't. After this it seemed to gradually run worst. I still have the cummins warranty so I decided to take it to dealership and have them work on it. They replaced the camshaft sensor and this helped it a bunch. Overall, it fixed the problem, except for when I'd take my foot off the clutch it will sputter for 2-3 seconds and then when you get up into 3 or 4 gear and accerelating it runs great. It also seems to do it worst when it idles, for example at stop light for 30-60 seconds. I took it back to the dealership that did the work and they believed it was water in fuel. So today I drained to tank and refilled it with some good truck stop fuel, and also changed the fuel filter. This did absolutely nothing. I should also mention when I start for the first time on the morning (45-50 degrees) it runs rough for 30 seconds or so and smokes white a little bit. In doing some research on this site it is sounding like an injector going bad. It has not thrown in codes to support this. Please help I am at a dead in. Thanks in advance.

 

I forgot one thing, it seems to be shutting down rougher that it was before.

 

In the past few days it seems to be getting a little better, except when it idles for a minute or two. For example, this morning I stopped at the gas station. I left it running outside while I went in for a 3-4 minutes and when I let off the clutch for the first time (in 2nd gear) it sputtered real. When I say sputter I mean it just cuts out and you have to give it gas to get up and running again. PLEASE HELP.

 

You said that you thought that it might be an injector, check your oil. I had an injector go bad on my 03 5speed and it leaked fuel into the oil which thinned the oil and ultimately broke my turbo shaft in half. I dont think this is your problem, but it is better to be safe than sorry.

 

I have no evidence to say it's the injectors, but from the little I have read on this site it sounds like a possibilty. The "diesel" guy at the dealership said that when an injector goes bad it probably won't start, and if it does it will run too bad to actually move the vehicle. Could it be the injector pump? Also, is the covered under the cummins 100k warranty.

 

i would take it back to the ***********.

 

what does that mean

 

If there isnt fuel in your oil, the easiest way to notice is the oil level rising, then its not leaking into the head, but when my injector went out the "diesel mechanic" had it for a week and after finnaly listening to my suggestions found it. No one else could feel the power loss but me and the only reason they believed me was that the oil level kept rising the leak was so small that you couldnt see it and they finally fould it by holding a piece of cardboad around all of the injectors running to see the fine fuel spray. I wouldnt rule out an injector misfiring though.

 

I just did the 3 key thing to see if it had thrown any codes, nothing. If it was an injector, could it be messing up without throwing a code.

 

Yes it is very possible when mine went out i did the key thing, nothing. I had no choice to run it home so bout 3 miles down the road I stopped and put my scanner on it, still nothing. Had it towed to the dealership for warranty repair, never a code. I know it sounds crazy but the truck never threw a code, not even a low boost code. Can you check your fuel mileage, if its all of a sudden very noticeably lower, my guess would be that an injector is staying partially or completely open when it should be closed. If thats the case the EGT should be somewhat higher. If the injector isnt working at all, im not sure what your fuel mielage would do, but the motor would definitely lose power, run rougher, be harder to start but would start and run, and could produce white smoke. But dont jump to conclusions, it could any number of problems, such as a slight boost leak, less than standard fuel, or many other things.

 

Relating to the guy above I have NOT experienced any type of power loss. It runs awesome once you get past the sputtering when first taking your foot off the clutch. Does this help?

 

I'm new here and searching for some answers also. I have an '03 CTD, auto trans, 4wd. I bought the truck w/ 170K about 2 months ago. It started sputtering at idle. Pull up to a red light and would have to hold foot on brake and excellerator to keep it from stalling. Had the LP changed. Was good for about 1 tank of fuel. It started sputtering again. Im not sure what direction to go in now. My mechanic disconnected my air intake and sprayed some form of cleaner in it. I think it was manufactered by "Mighty" Then added an injector cleaner from the same box to the fuel tank. It ran great for another tank of fuel. I noticed it is beginning to sputter again but not as bad.

 

It sounds like you and I are having similar problems. I guess the only difference is the fact that i have a manual and you've got and auto.

 

I took it back to the dealer today for the 3rd time. After a few hours and a call to Cummins the mechanic says my problems are being caused by the fuel actuator, which the way I understand is with the injection pump. It will be covered under the 100k warranty but the parts are not available until next week. Does this sound write to you guys?

 

My mechanic put my truck on the "motor vac" to clean the injectors. He told me that you have to hold the idle at 1500 rpms. About halfway through this process the rpms moved up to 2500 rpms. He responded by decreasing the throttle back to 1500 and held it there. After he completed the process, he stated the truck had a much better throttle response. We will see if this resolved my problem. I definitely felt a difference in the throttle response when I drove away from the shop. The mechanic told me this was the first diesel he had used the "motor vac" on to clean the injectors. I'll let you know if it corrects my problem with stalling.