What are the most common Hyundai Elantra problems?
According to Au7o's analysis of 456+ owner reports, the 2021 Hyundai Elantra has 5 documented issues. The most frequently reported are: Theft Vulnerability — Missing Engine Immobilizer ('Kia Boyz' / TikTok Challenge), Front Seat Belt Pretensioner May Explode and Project Metal Fragments (Recall 229), Phantom / False Automatic Emergency Braking and Forward Collision Activation. Of these, 3 are rated critical and should be addressed promptly.
Is the Hyundai Elantra reliable?
The 2021 Hyundai Elantra has 5 known issues documented across 456+ owner reports. 3 issues are rated critical: Theft Vulnerability — Missing Engine Immobilizer ('Kia Boyz' / TikTok Challenge) and Front Seat Belt Pretensioner May Explode and Project Metal Fragments (Recall 229) and Phantom / False Automatic Emergency Braking and Forward Collision Activation. Prospective buyers should inspect for these issues and factor potential repair costs into their purchase decision. Regular maintenance following the manufacturer's schedule helps prevent many common problems.
How much does it cost to fix common Hyundai Elantra problems?
Repair costs for known Hyundai Elantra issues range from $0 to $5,500, depending on the specific problem and whether you choose DIY or professional repair. The most critical issue, Theft Vulnerability — Missing Engine Immobilizer ('Kia Boyz' / TikTok Challenge), typically costs $0-$500 to repair. Au7o provides step-by-step DIY maintenance guides that can help reduce repair costs.
What is the 2016-2021 Hyundai Elantra Theft Vulnerability — Missing Engine Immobilizer ('Kia Boyz' / TikTok Challenge)?
Turn-key (non push-button) Elantras built in this range were sold without a standard engine immobilizer. Thieves can pry off the steering-column shroud, pull the ignition cylinder, and start the car using nothing but a USB connector tip and a screwdriver. The method spread virall… Repairs typically run $0-$500. Severity: high.
What is the 2021-2023 Hyundai Elantra Front Seat Belt Pretensioner May Explode and Project Metal Fragments (Recall 229)?
The micro gas generator (MGG) inside the front driver and passenger seat belt pretensioners can deploy abnormally during a crash. Instead of simply tightening the belt, the pretensioner can rupture and propel metal fragments into the cabin, striking occupants. The defect is tied… Repairs typically run $0-$0. Severity: high.
What is the 2021-2024 Hyundai Elantra Phantom / False Automatic Emergency Braking and Forward Collision Activation?
The Forward Collision-Avoidance Assist (FCA) and Blind-Spot Collision-Avoidance systems can trigger hard automatic emergency braking when no real obstacle is present. Owners report sudden, unprompted braking at 40-65 mph on open road, plus false activation when a vehicle passes c… Repairs typically run $0-$350. Severity: high.
What is the 2019-2023 Hyundai Elantra IVT/CVT Transmission Failure and Power Loss?
The Smart Stream IVT (Intelligent Variable Transmission) in newer Elantras has experienced early failures, sometimes before reaching 20,000 miles. Issues include sudden power loss, check engine lights, and RPM fluctuations. Hyundai issued TSB 20-01-047H addressing transmission co… Repairs typically run $0-$5,500. Severity: medium.
What is the 2011-2022 Hyundai Elantra P0420 — Catalyst Efficiency Below Threshold (Bank 1), Often Downstream of Nu 2.0L Oil Consumption?
P0420 on the Elantra means the downstream (post-cat) oxygen sensor sees the catalytic converter no longer scrubbing efficiently. On the 2017-2020 Nu 2.0L engine this frequently is not just an aged cat — it is a symptom of the well-documented Nu 2.0L piston-ring/oil-consumption de… Repairs typically run $300-$1,800. Severity: medium.
