Hyundai IONIQ vs Hyundai Sonata
Midsize sedan · 2015–2025 · 3,601 federal complaints

Hyundai IONIQ
1,607 complaints · 2 engines
Most-complained engine: Electric
Full breakdown for Hyundai IONIQ →
Hyundai Sonata
1,994 complaints · 3 engines
Most-complained engine: THETA-II · 2.4L I4
Full breakdown for Hyundai Sonata →At a glance
Side by side. EPA figures are the model's median across its test variants; price is the base-trim MSRP (CarAPI), median across covered model years.
| Hyundai IONIQ | Hyundai Sonata | |
|---|---|---|
| Base MSRP | $22,300 | $21,900 |
| Most common engine | Electric | THETA-II · 2.4L I4 |
| Induction | — | Naturally aspirated |
| Fuel economy | — | 31 MPG |
| Running cost | $750/yr | $2,000/yr |
| Low emissions | — | 291 g/mi |
| Cabin space | 105 cu ft | 106 cu ft |
| Cargo space | 11 cu ft | 16 cu ft |
| Displacement | — | 2.0 L |
| NHTSA overall crash rating | ★★★★★ (2025) | ★★★★★ (2025) |
| Rollover risk (NHTSA) | 6.7% | 9.7% |
| Engines with enough data | 2 | 3 |
Side by side
Both cars scored as percentiles within Midsize sedan, so the shapes are directly comparable. Built from EPA test data.
What each one's complaints are about
Showing each car's highest-volume engine. Share of component mentions — not a failure rate, and not a ranking between the two.
Hyundai IONIQ
Hyundai Sonata
How often each one's complaints involve a fire, crash or injury
Shares of each car's own complaints — sales volume cancels out of a within-car ratio, so these two can be compared. The vertical mark is the all-vehicle average.
all vehicles — Fire 1.1% · Crash 4.4% · Injury 2.6%
Every engine with enough data
Complaint counts per engine are shown for scale only — they track how many were sold, not how often they fail.
Hyundai IONIQ
- Electric1,464
- KAPPA · 1.6L I4Naturally aspirated143
Hyundai Sonata
- THETA-II · 2.4L I4Naturally aspirated1,708
- 2.0L I4190
- THETA-II · 2.0L I462
Recalls where NHTSA said stop driving or park outside
The severest recall class only. Model-level, manufacturer-confirmed. Recall repairs are free at any franchised dealer, whatever the car's age.
Hyundai IONIQ
- Electrical System › Propulsion System › Traction Battery (park outside, 2023–2024) 26V432000
- Electrical System › Propulsion System › Traction Battery (park outside, 2025–2025) 25V482000
- Electrical System › Propulsion System › Traction Battery (park outside, 2020–2020) 21V127000
Hyundai Sonata
- Service Brakes, Hydraulic › Foundation Components › Disc › Caliper (stop driving, 2015–2015) 14V368000
- Steering (stop driving, 2015–2015) 14V325000
- Power Train › Automatic Transmission › Fluid/Lubricant › Pump (park outside, 2023–2023) 23V526000
One car having more complaints than the other mostly reflects how many were sold, not how often they break. Compare each car's own mix of problems — not the totals.