ah hah
what you encountered was speed cut
you'll find when you drop the ecu that there is a pink wire and you have a little black box intercepting it
get that lead out of your foot
edit: any ideas what git stands for? just curious
but also odd... is yours an import? rhd or lhd?
uk cars i believe don't have speed cut but i guess maybe your ecu has been changed as some stage
if you do get the chance to drop your ecu would you be able to write down the part number on the ecu for me... i have a friend with a complete parts list so i can determine the originality of your ecu in particular
the speed cut is usually about 120mph