California Class-Action Says The Sonata’a Theta II Engine Knocks Before Failing

Contaminated oil is carrying metal shavings on a not-so-joyful ride through the Theta II engine leading to knocks, stalls, and eventual failures according to a recent class-action filed by a Sonata owner in California. [The plaintiff]_ brought [her] Sonata to a dealership and was told a piston had blown out. Mendoza asked for her car to be repaired under warranty, but the dealership refused to make the repairs. However, the dealer said the engine could be replaced for $4,500. Mendoza said no and took the Sonata to a mechanic and had the engine replaced at a cost of $3,000.

The plaintiff says she followed Hyundai’s recommended maintenance intervals and there was no reason her engine should have seized, you know other than the whole “doomed from the start” theory.

The lawsuit accuses Hyundai of concealing defect information about the connecting rods and metal shavings in the brand new engine.

The class-action covers 2011-2012 (6th generation) Sonata owners in California, but could set the groundwork for future litigation.

Want to Learn More?

Manufacturing Problems with the Theta II Engine Cause Knocking, Seizing, and Oil Sludge Buildup

The Theta II is a gasoline direct injection (GDI) engine that is well known for a lot of things and none of them are good. Bearing failure, metal debris riding on contaminated oil, piston ring defects, siezing, knocking, crying.