I wanted a second opinion, so some family members recommended Springs Auto & Truck, since they and they're friends had positive experiences with them. I brought my car to their garage. I have a p retty keen bull detector, and I can tell that these guys aren't going to rip you off (kind of like how the dealer tried to do to me). For no charge, they ran the test, and other extensive measures, he figured out that it was the O2 sensor. Several hours of his time performing the additional diagnostics, as well as installing the sensor. He told me to drive the car for at least 100 miles to reset its computer so it would pass inspection. After doing this, I brought my car to an inspection station and it passed with flying colors.