Your Elantra shakes at a red light, stumbles when you hit the gas, and the check engine light comes on. Classic misfire. Usually that's a cheap fix. On a few Elantra years, though, it can be an early sign of a bigger engine problem that Hyundai has already agreed to cover. Don't skip that check.
What a misfire feels like
- Rough or shaky idle, like the car is shivering
- Hesitation or a stumble when you accelerate
- Less power and worse gas mileage
- Check engine light, often with a code from P0300 (random) to P0304 (cylinder 4)
- A flashing check engine light, which means a severe misfire or, on some Elantras, the engine protection system kicking in
Normal causes and what they cost
| Fix | DIY | Shop (RepairPal estimate) |
|---|---|---|
| Spark plugs, 2022-2025 Elantra | Plugs plus a few tools | $320-$394 |
| Spark plugs, 2011-2016 Elantra | Plugs plus a few tools | $144-$297 |
| One ignition coil | Coil only, about 10 minutes | $204-$273 |
| Misfire caused by engine damage | Not a DIY job | Check warranty and recalls first |
RepairPal doesn't list plug prices for 2017-2021, so get a quote for those years. On newer Elantras, RepairPal notes the engine cover and coils have to come off before the plugs, which is why the price is higher.
The quick coil swap test
Got a code for one cylinder, like P0302? Swap that cylinder's coil with the one next to it, clear the code, and drive. If the misfire follows the coil (now P0303), you found your bad coil. If it stays on cylinder 2, it's more likely the plug, an injector, or something mechanical.
The Elantra engine campaigns to check first
2014-2016 Elantra (2.0 Nu GDI) and 2014-2020 Elantra GT: Hyundai's campaign extends engine coverage for connecting rod bearing wear to 15 years or 150,000 miles from original delivery, for original and later owners. Symptoms Hyundai lists include a check engine light with code P1326, abnormal engine noise, and no crank/no start. Hyundai strongly encourages the free Knock Sensor Detection System (KSDS) software update and treats it as a requirement for coverage. The 2014-2016 Elantra and 2014 Elantra Coupe were also in Hyundai's 2022 class action settlement over engine failures.
2019-2020 Elantra (2.0 Nu Atkinson engine): Hyundai Recall 203 covers Elantras with VINs starting "KMH" built through July 6, 2020. Some engines were built with out-of-spec piston oil rings, which can chip, scuff the cylinder walls, and burn oil fast. The dealer runs a free engine vibration test. If it fails, Hyundai directs the next step.
Easy things to try first
- Read the code. Parts stores often scan for free. A single-cylinder code is usually a coil or plug. P1326 is a different conversation.
- Check the oil level. If it's near or below the low mark soon after an oil change, tell the dealer. On 2019-2020 Elantras that's exactly what the piston ring recall is about.
- Check your maintenance history. Old plugs are the cheapest explanation there is.
- Run your VIN at nhtsa.gov/recalls and on Hyundai's owner site.
What to ask the shop before paying
- "Which cylinder, and did the misfire follow the coil when you swapped it?"
- "Does this VIN have the KSDS update and any open campaigns?"
- "Is this covered under the 15-year/150,000-mile extension?"
- "Are you using OEM-spec plugs?" (RepairPal stresses using the correct plug rating.)
Is it worth fixing?
A plug or coil job? Absolutely, it's routine maintenance. An engine problem on a covered 2014-2016 or 2019-2020 Elantra? Let Hyundai pay for it. Keep your oil change receipts, because they help with any warranty claim. Also dealing with a car that won't start? See our Elantra battery guide, or browse the Hyundai Elantra repair page.
Prices checked October 14, 2026.
