No problem...
Did it really get better or have you seen reprieves like this before?

Reason I ask is if it did get better you may be on the track of identifying the issue...I would also check the grounding to the chassis and body as I am not wholly convinced its not a grounding issue..

Aside from that the next thing that comes to mind is a possible BCM issue..
you could try to dismount and isolate it and see if that makes any difference...

 

I think it is better, the bumps have to be fast and strong now. Going to make some auxillary body ground cables this afternoon.

 

Its not better, tried extra body grounds, extra power source to fuse block, Symptom reveiw: bumps- cuts power intermintant, door locks activate, average econ deal and engine oil life monitor resets, abs lights come on, will die sometimes dependant on the severity of the fit, will sometimes go into reduced power mode, will sometimes not restart without unhooking the battery and when that happens the gear indicator light is not present so i think it can't tell if it is in N or P to let it start. after unhooking and hookin the batt. up it starts. Maybe I'll start buying random electrical parts off ebay and trying them.

 

Man its just not pretty at all is it...removing power is resetting the BCM...
might want to check any grounds that run to it...the BCM would be my would be my first shell in the chamber....
it might be worth a drive to the dealer for a sanity check....

 

I just can't do that, it would crush my wrenchin soul. Havn't reference automotive electrical diagrams before, only caterpillars (they get crazy too some have 5 ecms!!) but will gm grounds be all blk, or blk w/stripe, just wondered if they have a common denominator. Will check those bcm wires, but when I unhooked the bcm before, the ave econ display did not reset... in a spaz out it does???

 

Might check the ECM connector for any bent pins or corrosion.

 

ecm pins were clean straight and beautiful, tugged & twisted on every last wire while unhooked, all looked sharp there.

 

bcm checks out

 

after a week and a half of running fine it did it again, this time I found a broken ground wire at the back of the right head. Mission accomplished.

 

good job, fingers crossed that was the root...
is it something you could take a picture of the area it was in?