old thread but I've just encountered the same problem so just wondering where you used to ground your ECU?
(I recently installed a lithium battery so had to remove some of the spacers around the battery tray - I suspect that while doing that I may have incorrectly attached the ECU ground to battery instead of the right location).
2004 Ducati Monster S4R
2004 Buell XB12S (daily hack)
2000 Yamaha FZS 600 (before they went soft)
1998 Yamaha Virago XV1100 (to be cafe'd)
1998 Honda VLX 600 (to be bob'd)
2004 Vespa 150 (bored out to 180 with race-cam and exhaust and Ö SIDECAR)
2004 Audi S4 (mountain / ski pony)
1999 VW Passat v6 4Motion (slightly cheaper to run than the S4!)
1972 Toyota FJ40 (frame-off restoration for the Zombie Apocalypse)
AC Cobra - 60% complete (just for shits and giggles)