Diesel Bombers

Diesel Bombers (https://www.dieselbombers.com/)
-   Diesel In Distress - Support Ticket (https://www.dieselbombers.com/diesel-distress-support-ticket/)
-   -   '05 Cummins Rough Idle/Sporatic RPM's. NEED HELP!!! (https://www.dieselbombers.com/diesel-distress-support-ticket/84653-05-cummins-rough-idle-sporatic-rpms-need-help.html)

North Pole Hooker 11-23-2011 09:13 PM

Alright, this is what the reflash said: The #4 injector is acting up. So, putting in a new injector should fix it, right? NOPE! A new reflash and a new #4 had it doing the same crap, however, it DOES idle a LITTLE smoother. A VERY little. Just how bad can an injector get before it throws a code? If he'd had the money, he would have replaced ALL of his injectors, but he's as poor as our national economy at this moment. What's next? Anyone?. Anyone? Vinny?

Vinny, I'm gonna either call you, or have him call you AFTER the Holiday. Happy Thanksgiving, everyone. Hard to be FULLY happy with a limping diesel!!! :argh::argh::argh:

el jefe 11-24-2011 12:53 PM

Replace all the injectors, check the fuel pressure to make sure pump isn't crapping out. Could he of got a bad tank of fuel? Anything added to the fuel?

North Pole Hooker 11-24-2011 06:47 PM

It's not bad fuel, been like this for months (multiple tanks through diferent stations). Nothing is added to his fuel (2 stroke oil, cleaner, cetane booster, etc.). And replacing ALL of his injectors is pretty much out of the question for a while, as he doesn't make that much money (E-5 Army Soldier). His Airdog 165 is sitting in my garage, gonna put that on maybe this long weekend. Would be awesome if THAT did it. If it doesn't, there's not much left to replace in the fuel system other than the CP3 pump, itself. FCA is new, already. Keep sending me ideas and y'alls knowledge, though. I / we need as much help as we can get!!!:tu:

wildbill 11-24-2011 07:32 PM

What you can try is ohm testing the injector solenoids. Pretty easy to do :)

Unplug all the injector harness connectors
Remove the valve cover (be two pieces, black plastic box and an aluminum cover)
Remove the 2 nuts from each injector solenoid
Wipe the terminals clean and test each one (ohm meter as low as possible. 20 is good)
If they test more than 1.0 ohm, the injector is bad. .4 to .7 is preferred. :tu:

North Pole Hooker 11-24-2011 08:17 PM

That's what I'm talking about, someone giving me some actual troubleshooting proceedures!!! Awesome, thanks! Gonna give that a shot tomorrow after all of this Thanksgivving turkey runs its' course! Thanks, Wild Bill!

The check is between the two terminals on the top of each injector, right? Not the wire harness itself? This is done with the engine off for sure. Is there a ohm number for checking the harness as well? If the Airdog doesn't fix it, it's GOTTA be electrical!

North Pole Hooker 11-25-2011 09:40 PM

Well, the new Airdog II DF-165 didn't do anything for it, so it's not fuel pressure. We are still going to try the ohm check, Wild Bill. Thanks again for the troubleshooting info. That's always what I'm looking for! :c:

tomduelly 11-26-2011 06:03 PM

clean every ground connection on the truck you can find, the ECM's do all their switching on the ground side ,and a bad ground in one place will try to find a path somewhere else and cause problems on the way.

cummins_guy 12-06-2011 07:45 PM

check compression

check valve lash

check push rods

does motor shake at low rpm's and smooth out at higher rpms? (keep in mind that it a diesel, yes it will shake but is it normal)

MillerBoyzDiesel 12-14-2011 08:18 AM

i would check injector returns, get a measuring cup or somthing else that has ml or cc units, you need to take the cp3 pump return line off at the pump then disconect it at the rubber hose after that reinstall the metal banjo line and bolt back into the pump and attach a hose to the end of it and route that hose to a empty container. Reach through the wheel well opening and disconnect the return line quick connect and attach another hose to the metal fitting that u removed the return line from and route that hose into your measuring cup, crank the truck over some until u get a little fuel dripping out into your cup. then start and run truck for one min. at idle you should have no more than 180ml/cc of fuel in cup after one min. if more then try retightening all 6 of the fuel tube nuts and re run test. I would say you wont have more than 180, probly will be 50 or 70 ml coming out if that is the case the truck will need new injectors minus the #4 you have already replaced. The fuel you collect out of the pump you can just pour out or back in the tank, if you want you can measure this amount and it should be less than 1000 ml/cc but a cp3 output test is more effective for checking the pump than checking its return flow, to run this test hook everything back up. unplug your fca disconect the pump feed line going to the rail and put a hose on the pump outlet and into your measuring cup, crank in 3 10 second intervals and you should have no less than 70ml if less and you are sure you have plenty of fuel entering pump then you need to replace the cp3


All times are GMT -5. The time now is 02:54 PM.


© 2024 MH Sub I, LLC dba Internet Brands