Table 1 shows three common engine and engine cooling related problems of the 2021 Hyundai Sonata. The number one most common problem is related to the engine and engine cooling (52 problems). The second most common problem is related to the gas recirculation valve (egr valve) (three problems).
| Problem Category | Number of Problems |
|---|---|
| Engine And Engine Cooling problems | |
| Gas Recirculation Valve (egr Valve) problems | |
| Coolant Leaking problems |
At approximately 130,000 miles, vehicle developed and internal coolant leak caused by a failed exhaust heat recovery system (ehrs) in the center muffler assembly, matching TSB 23-em-009h - a known manufacturing defect documented by Hyundai. Read details...
2021 Hyundai Sonata 59,850 miles rpm jumps to around 1,300 at zero miles on occasion. If I am stopped, at a red light or behind other stopped autos, the vehicle jumps forward when I take my foot off the brake. Read details...
Hyundai technical service bulletin 23-em-009h (ehrs coolant leak) - aka a faulty heat exchange that causes the coolant to leak into the exhaust and burn away. Resulting in a very hard to diagnose coolant disappearance. This should be a recall. Read details...