Hi

i have 94 caprice wagon with lt1

i tried to adjsut my speedometer because i was a bit off, (shows 70 mph when gps is 52) i found some spreadsheet what to use for calculation and download orginal bin file from the car using C.A.T.S flash program, first i had some difficulties to get connection, some error came but i reboot my computer and it helped.

went to tunerpro and change those 3 values for speedometer, save file wihth new name and opened flash program again...

then i tried to reprogram my ecu, program connected, started to erasing flash memory but suddenly i got error message about some violation and writing stopped and canceled...

now i cannot get connection back again and my fault light is on in dash...

been trying few things, reboots, resets, but no luck at all.. what to try next