The tech should have told you there more to it than just driving a bunch of miles. There are six Drive Cycles, and some have very specific requirements you have to meet. Like DC 1 requires you to have less than 2/3 tank of gas. So when you have time to mess with it, go to the free factory service manual at tearstone.com and check out the Drive Cycles listed in section 13B page 10. Use your OBD reader to figure out which Drive Cycle you need to complete, then go execute the DC how ever many times it's required.