The 2018 Sonata continues the 7th-gen Theta II engine concerns. Hyundai extended powertrain warranty (10yr/120K) for affected engines and issued the KSDS recall. Bearing failures remain the dominant issue.
Same Theta II bearing failure risk as 2017. Extended warranty and KSDS recall in place. Verify all recalls completed and engine history before purchase.
Same bearing failure pattern as 2017. Listen for knock, monitor oil pressure.
View P1326 Diagnosis →Turbo variant also affected.
View P1326 Diagnosis →Verify completion before buying.
View P1326 Diagnosis →Bluetooth and Apple CarPlay drops. Updates address.
Run free diagnosis →Some 7th-gen Sonatas have early AC compressor failures.
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Avoid unless engine has been replaced or you have full warranty coverage. The Theta II issue is too widespread to ignore.
No - 2018 carries the same Theta II issues as 2017. Even with the warranty extension, ownership friction is significant.
Expect $400-700/year in routine maintenance. Engine replacement risk is the wild card. Lifetime non-routine cost varies widely based on warranty coverage.
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If your 2018 Sonata is throwing a check engine light, these are the codes most often associated with the problems above. Click any code for full diagnosis steps and typical repair costs.
Below average due to Theta II engine bearing failures. Hyundai extended powertrain warranty to 10yr/120K but the underlying issue persists.
For 7th-gen cars, no - the underlying design is unchanged. The 2020+ Smartstream engine is a different design.
Only with documented engine replacement or full warranty coverage. Otherwise, look at a 2020+ 8th-gen Sonata.
A Hyundai dealer can pull warranty history by VIN. Always verify before buying.
If the engine survives the bearing-failure window or is replaced, 200K+ is possible. If not, lifespan can be cut short dramatically.