Q: Check engine light and P0139 code on a 2006 Hyundai Coupe

You’ve got to realize that those things often pretty much weld themselves in. From the difference in the metal and the sensor, and the metal and the exhaust. I use special sockets that fit on them, which anybody can buy. They cost 8-10 bucks a piece. Then I use a long extension bar, we call them cheater bars that fit on the socket. I pull like mad and it almost always makes them loose. If it doesn’t break them loose, then get yourself a little torch and heat it all up until it’s red hot and then it will always come off. Heating metal red hot always makes it nice and slippery inside so it would come apart. You’re going to replace it anyway so it doesn’t really matter if you heat it up and ruin up the old one because you are throwing it anyway. If you want to have your Check Engine Light issue diagnosed and taken care of, a technician from YourMechanic can come to your home or office to perform this task for you.