I thought I would post this question here, as so far no one from my resources has been able to help me, and thought some may find it interesting.
ISL, CAPS, CPL 8042 in New flyer D40LF Transit bus. ECM code J91144 24VDC 15,000 miles
Smokes and runs rough at start up and logs intermittant 276 fault code until timing shift occurs. After initial timing shift will not log any faults and will run the rest of the day. Sometimes it runs so bad that you never here the audible timing shift, and will continue to run bad until it is shut off for fear of breaking something.
I have isolated the alternator, run unswitched power and grounds directly to the battery posts. I have changed the stator on the ICV, transorb diode,wiring harness and ECM, new batteries. Checked snubber for debris all was fine.
Have you ever seen a mechanical problem in the CAPS pump cause a 276 fault? And if so what was it? What am I missing?
Going back to work on it in the morning and will try to see if it is temperature related. Fuel pressure does fluctuate some but I am sure that is do to the wide RPM surges at idle and the fact that it almost dies several times but doesn't. Also I have more than one unit doing this.
A Johnson
ISL, CAPS, CPL 8042 in New flyer D40LF Transit bus. ECM code J91144 24VDC 15,000 miles
Smokes and runs rough at start up and logs intermittant 276 fault code until timing shift occurs. After initial timing shift will not log any faults and will run the rest of the day. Sometimes it runs so bad that you never here the audible timing shift, and will continue to run bad until it is shut off for fear of breaking something.
I have isolated the alternator, run unswitched power and grounds directly to the battery posts. I have changed the stator on the ICV, transorb diode,wiring harness and ECM, new batteries. Checked snubber for debris all was fine.
Have you ever seen a mechanical problem in the CAPS pump cause a 276 fault? And if so what was it? What am I missing?

Going back to work on it in the morning and will try to see if it is temperature related. Fuel pressure does fluctuate some but I am sure that is do to the wide RPM surges at idle and the fact that it almost dies several times but doesn't. Also I have more than one unit doing this.
A Johnson
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