I have a 15 year old VMSpc unit on a 2001 Cummin's engine. It has worked perfect but my old Toshiba gave up and I had to replace it. The new laptop works fine with the VMSpc program but my fuel usage calibration is out of whack. The old computer had it to 99% accuracy but I forgot how to adjust the program to calibrate it. Please help me. I show 9.1 mpg and actual is 8.5.
Also where can I get a manual for my unit?