I just want to throw this out there for people in case they run into this issue. A week ago my data logging laptop gave up the ghost and the lcd went out. not being cost effective to fix I bought a new to me laptop. Its a toshiba A505 with a bad hard drive. after replacing the hard drive and reloading the factory software and tuner pro I went out and started datalogging again. after a couple days of logging and making corrections I started to notice the tune was getting worse not better. upon futher inspection of my logs I found breaks in the time sometimes 2 seconds or more of data was missing. I tried different ADX files, multiple reboots, and differnet drivers. about fed up with this laptop after banging my head against it for 2 days straight I smacked the keyboard while trying to record data, low and behold the log paused for a second so I smacked it again and the same thing happened. after further research I found this laptop has a HDD protection program running on it that was parking the heads of the hard drive when it detected vibration (assuming bumps in the road). from the manufactures site:
"Using the acceleration sensor built in the PC, HDD Protection detects vibration, shocks and similar signs in the PC, and automatically moves the Hard Disk Drive (HDD) head to a safe position to reduce the risk of damage that could be caused by head-to-disk contact."
To make a long story short if you have this feature it would be wise to disable it while datalogging if you have a rough riding vehicle...