There could be other reasons than injectors. Though the DRBIII does go a long way in identifying leaking injectors (etc); the dealer could be right.
I've just finished fixing this type of problem in mine. What happened was that it became harder to start (seemed to sneak up on the start, so to speak, cranking faster until it finally 'caught'). It would start warm, but not cold. It gradually got worse until it would not start on it's own, at all.
I'd quickly discovered that it would start with ether...
Then I started noticing my fuel pressure gauge dropping. At first, I was thinking filter... then, well, perhaps the LP (put in another carter). Well, everyone knows they're junk so perhaps that second one was bad too. . etc, etc, etc.
Well, not too long ago with the fuel pressure dropping to zero more frequently, and then a very slow recovery to 3psi at idle, perhaps 6psi when cold... it had finally reached the point that I had to do something. I was concerned I'd toast the CP3 for lack of sufficient fuel to cool it.
Right about here, during an oil change, I was pretty sure I could hear what sounded like fluid under pressure 'squirting' (as in a high pressure stream) while the engine was running. Hard to be sure with the noise of an idling engine, but I was sure enough I couldn't let it pass. It concerned me that there might be a cracked or leaking injector, and what it could do (dilute the oil, burn a hole in the piston, etc).
So - I had to figure it out. I looked around, found a place with good references among the Dodge/Cummins crowd around the Portland area, and took it to the shop. They thought injectors too, so that's what went in first. They flushed the system, changed the filter, put in new injectors, and it started. That may have been a coincidence, as it went back to not starting within 2 days.
So, still seeing this troublesome low fuel pressure, I found a good price on a Raptor 100GPH pump, and that puppy brought 'er right back up there to 12 psi cruising at 65+. Still seemed a little mushy (dropping some on heavy acceleration). . but at least I wasn't starving the CP3 and the pressure was acceptable.
I got a little time today, so arranged to run it back down to Oregon City and do some more diagnostics at the shop. They put it on the DRBIII, looked at all the usual stuff, loading across cylinders, turning off one injector at a time, checking codes, etc. All looked normal, including idle pressure on the rail.
So, going down the list of possibles, the first thing they tried was the pressure relief for the rail - which has a return line back to the filter assy (and probably to the return to the tank).
Fired right up just like the first time I started it. . that little thing costs $400, but evidently it was leaking enough to keep the rail from reaching sufficient pressure during cranking to start - until the ether gave it enough additional crank RPM to clear that hurdle.
That leaking thing was also why my LP appeared weak, the CP3 was moving enough additional fuel through the LP, filter, etc to not only reach the target rail pressure and feed the injectors but to also feed the leaking pressure relief. . and the sound of that fuel being released at rail pressure (~5k psi at idle) back into the tube that returned to the fuel assy was the source of the squirting sound I'd heard.
So - turns out that little gem is an alternative source to consider as the cause of your hard starting problem.
Oh... and now, that Raptor pegs the 15psi fuel gauge at idle, and drops very little under acceleration (heavy or otherwise); I don't recall exactly from the drive home - perhaps a 1. 5-2psi range now, as opposed to a 4-6 psi range when the relief valve was leaking.
So - that's my story.
Got a nice set of injectors from DonM, a lighter wallet, and a sweet running engine that starts right up...
Go figure.
Mark
Im looking at a 2003 common rail that has aprox. 171 k. The price is somewhat right but there is an issue with the truck starting. It will not start on its own, however if you shoot a ½ of a shot of ether into the air cleaner it starts right up and runs and drives beautifully for however long it needs to. He was told by the local Dodge stealership that it needs injectors but after talking to a few people myself, a few of them seem to believe that it is the in-tank pump that is bad and once it runs on the ether for a few seconds the low pressure side of the injection pump is drawing the fuel thru the tank pump.
Has anyone here had a similar experience?
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