need some help.  have an 03 ram 3500.  first off has a lurching problem.  truck will haul ass for a couple seconds then die out for a couple seconds.  will repeat for a few seconds then run fine.  totally spurratic on when it decides to do this.  will be fine for a few weeks then keeps doing it for a week or so.  cold or warmed up.  been going on for last 3 years.  then died completely in june.  Had 2 bad injectors in front bank, so replaced those.  still wouldn't run.  next replaced ecm.  mechanic has talked to dodge tech and cummins tech.  they said ecm or wire harness or injectors.  mechanic has also checked harness over and over again.  still wont run.  since new ecm won't kick up any codes. turns over but won't run.  mechanic says no mechanical reason why truck won't run.  need help getting her back on the road.  anyone have any suggestions?? any help or ideas greatly appreciated! don't know what else to do with it.  

Check the lift pump to see if you're getting fuel to the filter, then the injector pump.  If you have bad injectors it will be more due to not getting enough fuel to them more than anything.




Kris  

Kris,

Had to create a new login.  Mechanic says it has fuel pressure so there should be enough fuel going through for it to start. ??  We've got a ppc cp3 lift pump plus a fass fuel pump.  Do you think the fuel line might need to be bled then, air in the line?  thanks  

What about a CSP sensor. Crankshaft or camshaft position sensor. Don't rule that one out.  

Good call on those sensors, those could also be the source of the problem.

If you crack the fuel filter open a little bit and turn the key off and on a few times, the lift pump will prime the filter and you'll know if you're getting fuel at least to the filter.  If you have any stored codes they should display on the odometer when you do this as well.

Try that, and have those sensors checked, and let us know what you find.




Kris