Kia Optima Plug In Hybrid
Problems & Worst Years

Engine trouble tops the list for both model years of the Optima Plug-In Hybrid in this data, though 2018 edges out 2019 on nearly every measure: 143 total complaints against 108, 17 distinct problems against 10, and four safety-severity complaints against two. Engine misfiring paired with outright failure was the single most-reported issue in 2018 at 29 occurrences, with oil consumption close behind at 26; a headlight malfunction added 18 reports, and a steering column coupler failure was reported 13 times at high severity. Paint peeling and bubbling rounded out that year's top five with 10 reports, a cosmetic complaint rather than a mechanical one but common enough to make the list.

Oil consumption became the dominant theme in 2019, appearing twice among the top five under different wording for a combined 50 reports, both rated high severity. A forward collision avoidance system malfunction, reported 16 times, carried the safety-severity tag and was the year's most serious recurring complaint. Spark plug issues (9 reports) and a repeat of the paint peeling and bubbling complaint (9 reports) filled out the remainder.

No recalls apply to either model year in this dataset, so buyers should lean on independent inspection rather than assume a manufacturer fix has already been applied. Given how consistently oil consumption and engine misfire complaints appear across both years, an oil-consumption and compression check during a pre-purchase inspection is a reasonable ask regardless of which year is under consideration. These are, in the end, owner-filed reports rather than a scientific defect rate — the newer 2019 car has simply had less time to accumulate its own complaint history — and a full service history will tell a prospective buyer more than the model year alone.