One problem related to gas recirculation valve (egr valve) has been reported for the 2012 Hyundai Tucson. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2012 Hyundai Tucson based on all problems reported for the 2012 Tucson.
I was driving and the engine started making a noise. All of a sudden it sounded terrible like there were rocks rattling around in the engine and it shut down. I was initially in town when it started and just got on the hwy when she broke down. Hubby, two puppies, and I were stranded in the side of the hwy in 100 degree heat for 2 hrs. Had to rent a moving truck and trailer to make the trek back home to GA. Hyundai service said it threw a rod and shredded in the engine and the entire engine needed replaced. Minimum of $5500 for the engine itself. I switched to synthetic oil on the first change when I got her new and was regular with her maintenance. I was not ready to have to get a new vehicle just yet.