Here are Hyundai Sonata engine problems, by model year. The most common Sonata engine problems cost $5,600 to fix & occur at 87,000 miles. Regarding the worst model year 2011 Hyundai Sonata engine problems, "The 2011 Sonata has a seriously defective engine that seizes without warning. It was awarded the dubious honor of being the first CarTalk / CarComplaints Turd of the Week in late September 2015." Click on a year below.

Worst Engine Problems
engine seized 2011 Hyundai Sonata
engine seized 2012 Hyundai Sonata
engine seized 2013 Hyundai Sonata