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JoeHEB1
Advanced Member

498 Posts

Posted - 10/07/2014 :  09:09:50 AM  Show Profile  Visit JoeHEB1's Homepage  Reply with Quote
I have a 444E that is making my blood pressure rise! It has no power and idles rough for about 5 seconds then smooths out for about 2 seconds then rough again and smooth again. I've checked for codes and the codes say right bank shorted, performed a buzz test and says injector #8 is shorted. I've replaced all injectors, replaced right side valve cover gasket and harness, repaired left side #6 injector harness connector and replaced burnt valve cover gasket, I've also swapped ECM,IDM,CMP sensor and injector harness from sister bus, checked the entire harness from the battery box to the engine. Hope someone can chime in on what to do next besides removing key and insert new bus. Thanks..

RonF
Top Member

867 Posts

Posted - 10/07/2014 :  09:30:13 AM  Show Profile  Reply with Quote
Engine wiring harness from the IDM to the pass through connector possibly.

US Army retired CMBT
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JoeHEB1
Advanced Member

498 Posts

Posted - 10/07/2014 :  10:41:57 AM  Show Profile  Visit JoeHEB1's Homepage  Reply with Quote
Yeah forgot to mention that, swapped ECM/IDM harness as well.
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Derbybug
Senior Member

USA
59 Posts

Posted - 10/08/2014 :  06:17:04 AM  Show Profile  Reply with Quote
Did you check the UVC harness connections after they were replaced? The $.50 fix may help you if the harnesses are loose.

Safety in all things, always!
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JoeHEB1
Advanced Member

498 Posts

Posted - 10/09/2014 :  05:11:12 AM  Show Profile  Visit JoeHEB1's Homepage  Reply with Quote
UVC connections are good.
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aaronwilmoth80911
Top Member

538 Posts

Posted - 10/09/2014 :  11:49:42 AM  Show Profile  Visit aaronwilmoth80911's Homepage  Reply with Quote
Have you done anything else on it besides what you listed?
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JoeHEB1
Advanced Member

498 Posts

Posted - 10/09/2014 :  1:19:56 PM  Show Profile  Visit JoeHEB1's Homepage  Reply with Quote
quote:
Originally posted by aaronwilmoth80911

Have you done anything else on it besides what you listed?



Haven't had a chance to do anything else to it. Still banging my head on this one.
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aaronwilmoth80911
Top Member

538 Posts

Posted - 10/10/2014 :  05:57:54 AM  Show Profile  Visit aaronwilmoth80911's Homepage  Reply with Quote
Is the check/warn engine light on when it does this? If so, what code numbers are you coming up with?
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JoeHEB1
Advanced Member

498 Posts

Posted - 10/14/2014 :  05:18:54 AM  Show Profile  Visit JoeHEB1's Homepage  Reply with Quote
Yes the engine light comes on when it idles rough then goes out when it smooths out. Codes say right bank shorted out and the injector test shows #8 injector shorted to ground.

Update: noticed that the engine runs fine once it reaches operating temperature, replaced thermostat and ECT sensor and it still does the same thing on cold starts.
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RonF
Top Member

867 Posts

Posted - 10/14/2014 :  08:19:11 AM  Show Profile  Reply with Quote
Runs rough on cold starts... replace your injectors or injector o rings. I have done many of these for this same problem.

US Army retired CMBT
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JoeHEB1
Advanced Member

498 Posts

Posted - 10/14/2014 :  08:43:43 AM  Show Profile  Visit JoeHEB1's Homepage  Reply with Quote
Injectors have been replaced, problem remains.
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RonF
Top Member

867 Posts

Posted - 10/15/2014 :  09:32:39 AM  Show Profile  Reply with Quote
Shot it!!!

US Army retired CMBT
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RonF
Top Member

867 Posts

Posted - 10/15/2014 :  09:39:54 AM  Show Profile  Reply with Quote
Glow plugs? Glow plug relay?

US Army retired CMBT
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JoeHEB1
Advanced Member

498 Posts

Posted - 10/15/2014 :  10:49:12 AM  Show Profile  Visit JoeHEB1's Homepage  Reply with Quote
Glow plugs and relay are fine.

Plugged in block heater for a couple of hours and cranked right up drove just fine. Let it cool down for a few hours and it ran rough then smooth then rough and so on. Runs good when it's at operating temperature. What gives?
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JoeHEB1
Advanced Member

498 Posts

Posted - 10/20/2014 :  06:38:13 AM  Show Profile  Visit JoeHEB1's Homepage  Reply with Quote
Update: wouldn't you know it! Injector #8 gave up the ghost again! I ran the engine with valve covers off and disconnected each injector one at a time to see if the engine would smooth out, and sure enough #8 smoothed it out. Replaced the injector under warranty and now it runs good on cold starts. That is the third injector that has gone out in that same #8 spot. How can that be? Thanks for all your input.
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