Check a VIN

May 19, 2026 Service campaign

Following completion of Service Campaign 9C2 (Theta II Emissions Improvement), certain vehicles may...

Hyundai technical service bulletin 9C2 DCS 260518 for 2015-2019 Hyundai Sonata, 2019-2020 Hyundai Santa Fe and 2018-2021 Hyundai Tucson and others.

Bulletin number
9C2 DCS 260518 (9C2)
Component
Engine
Summary
Following completion of Service Campaign 9C2 (Theta II Emissions Improvement), certain vehicles may exhibit a brief hesitation or rough shifting condition during cold start operation. If present, this condition is expected to occur only within approximately the first 1-3 minutes after engine start, while the catalyst is reaching its normal operating temperature.

Owners of these vehicles have filed 2,996 complaints in the engine category.

Vehicles covered

VIN decoder

See the problems and recalls for an exact car

Buying a used Hyundai Sonata?

Check the exact car before you pay: accidents, salvage or flood titles, odometer readings and previous owners.

Check its history