I am working on a 2003 Common Rail that will not start. It has been getting worse for the past few weeks, but now it won't start. It will start on either and then run just fine after that. You can shut it off and it will fire right back up, but if you let it set for about an hour, it will not restart w/o either. It is like the electronic side of this is not telling the injectors to fire. It is getting fuel to the rail (injectors). I had thought that ie it had a bad injector that was back feeding and not letting the others fire, but i unhooked one at a time, but that didn't change anything. You can leave on unhooked and snuff it and it will fire, but still not on its own. I do not know what the fuel PSI is yet. Both the Crank and Cam sensors are good (checked with an Ethos Scanner), and the fan hub sensor is ok because there is no codes. I am not new to working on diesels, but this one is getting to me. If anybody knows anything that would help get me going again, it would be greatly appreciated!!
Thank You - Jay

 

Well my first suggestion would be not to crank those fuel lines anymore while you have the engine running the fuel psi that is stored in the rail and transferred to the injectors I have personally seen get into the 100,000 psi range which exposing yourself to those pressures it not safe, but anyways back to your problem. If the engine will start and run off of either and then run fine you arent looking for a ecm issue where it is not actuating the injectors. In that fuel system there is a check valve that is supposed to hold fuel in the rail so after long periods of setting and not running the engine will start easy. I would start there and I would also confirm that the lift pump is operating correctly.

 

Thank you very much for the info! I will start there and see what I can find. I just found that if it sets for more than 15 minutes, then it will not start, but if it is less than 15 minutes, it will still restart. The longer it sets (up to 15 min.) the harder it will start. The part about the unhooking the injectors I was not clear enough on. I unhooked the wires on top, not the fuel line (sorry about the mix-up). I was told that if it was a bad injector, it would let it run when the bad one was unhooked. It did not change anything. I pulled the injectors and they are on their way to Ft. Wayne Diesel to get bench tested, in case one is dripping. I don't know why they did it because the truck only has 67,108 miles on it!? I will check the other items and go from there. I greatly appreciate all of your help!! Thanks - JAY

 

the injector tubes might have been alittle loose I have seen it on a few trucks with this problem and quit using ether.

 

the ECM has to see a certain psi before it will let the injectors fire. if a crossover tube, rail relief valve, or injector is leaking it will let enough fuel escape the system so that the pressure doesn't get high enough for the injectors to fire. but ether gives it enough rpm to make the pressure and start.

 

This is in reference to my '03 Cummins starting issues. I ended up sending the injectors out to get tested. Ft Wayne Diesel Svc. said they were bad and were not flow the right amount of fuel. Si I bought a new set and it solved the problem. It fired right up, I let it set overnight and it fired as soon as I hit the key. I wanted to say Thanks again for all of your help in this.
Thanks - Jay