If you're having trouble getting it to work try running a large magnet across the sensor as you're letting air out. I do this on the Vette and don't even need to let any air out but I do on the truck. I have a friend's truck where I can just use the magnet, so I'm guessing there are differences in the TPMS that's making it easier for some than others... I got a big magnet from Harbor Freight for ~$5 that works great. An old speaker magnet would work well too.