Bests & Worsts Reviews from Amazon

This device saved me when my CA smog check came up. Have a Nissan Rogue that is driven almost exclusively on streets. Wouldn't pass smog when first checked as some of the sensors had incomplete data. A mechanic offered to charge me a bunch of money to diagnose what was wrong, but a web search revealed that I could resolve the issue myself. The web pointed me to this type of tool along with a reset procedure to get the vehicle sensors calibrated. I first used this device along with Torque software on my phone to verify the smog center's reading, and then to check the vehicles emission monitors as I drove ~200+ highway miles to complete the sampling data. I was able to monitor the car's emission computer real-time readings and see the point where all of the sensors had the data needed to pass the smog test. Cost of this device with software was about $30. The mechanic was going to cost ~6 times that. Device and software worked well, no issues. Reader was easy to attach and connect to my phone via bluetooth. Now that I've used this device once, I feel that it is an essential tool if you have an older car and mandated smog checks. If you have any doubt about your vehicle passing I recommend using this device or one like it _before_ you spend money on a smog check. Would buy again.