HP Automotive has state of the art diagnostic capability. They quickly pinpointed the issue that triggered the CHECK ENGINE light on my commuter car with more than 100,000 miles. This was not one of those false alarms caused by the gas cap screwed on wrong, as I first suspected. HP Automotive identified an issue that impacted the car's daily operation, it's longevity, and posed a small but real safety risk to anyone near the car. Addressing the problem early saved significant money in the value of the car. Thanks HP Automotive.