Q: Needs to be replaced, need to know where to find it. Thanks!
A: Crawl under the jeep driver's side. Go toward the front on drivers side of the engine an look at the exhaust pipe as it approaches the exhaust manifold. You will see it hanging out, usually to the outside of the truck with a 12" wire going to a connector. It will unscrew from there. Be Very careful with the new on as the ceramic prob is easily broken. Coat the thread in never seize compound and reconnect the wires. Make sure they do not touch the exhaust pipe or they will burn through. Good Luck