Yes u can datalog with it eric. As far as accuracy I'm not sure but I have used it to check eot/ect on trucks I or a buddy have gone to look at and it appears to be pretty good. Checked it on a truck with a brand new oil cooler and eot/ect were within 5* during the test drive. Checked another truck with 100k on the oil cooler and they were 12-15* apart. Curious to see if anyone has actual ect/eot gauges that they could compare it to.