My 2017 Hyundai Elantra Keeps Misfiring and I'm Frustrated

For some background, my 2017 Elantra first started misfiring in 2019. I always replaced the spark plugs myself, and that would fix the issue. Since then, it’s misfired 1-2 times a year. This year, it started misfiring again after I changed the spark plugs, and it was good for about a week before the same problem returned. I then replaced the coils, and it seemed to drive fine after that.

This spring, while driving in slow traffic on the highway, my car stalled out of nowhere! After that, the stalling happened frequently, and my car would shake while the engine became very loud, which was quite scary. I took it to a repair shop, and they thought it might be something with the timing but eventually said I’d need a new camshaft or engine. I decided to get a second opinion at a Hyundai dealership. I don’t recall what they did, but it turned out to be a simple fix, taking them about a month to figure it out. After that, the car worked well! I even drove it from Colorado to Virginia without any issues. I’ve kept up with regular maintenance and take care of my car.

Now, just this week, it’s started misfiring again! I believe there’s a bigger issue, and I’m getting fed up with these problems. I’m at 99,710 miles, so thankfully I haven’t hit 100k yet! Is it worth trading it in for a new car? I would really appreciate any insights and advice!

Why risk it? Trade it in and get something more dependable.

Brandy said:
Why risk it? Trade it in and get something more dependable.

I just hate the idea of buying a new car. The Elantra is paid off, and not having a car payment is great for both my husband and me.

@Dany
Do you have paperwork from the original dealership repair? (The one that took a month but ended up being a simple fix).
If your car is reliable otherwise, you might want to find out what they did and do it again. Even if it’s something you have to repeat occasionally, it could be worth it. If that doesn’t work and you can’t find an easy fix, then maybe consider trading it in.

@Jason
I’ve been trying to call them all week to get them to email me, but they haven’t answered. Their voicemail box is full. I plan on telling the dealership I’m going to next week to reach out to them before they start working on anything.

@Dany
Good plan! Sometimes it’s best to be patient and wait it out. It reduces the chance of regret later.

@Dany
I get it. I recently traded in my 2013 Elantra GT (fully paid off) for a 2020 Kona (financed) because I preferred the certainty of costs rather than an unknown future repair bill.

My aunt has a 2017 Elantra too, and her engine was replaced at 30k for the same issue. It’s really scary when your car cuts out in traffic. First thing to do is contact Hyundai and file a claim. I suggest working with the dealership and standing firm with Hyundai America since this is a documented issue. Why give up when this isn’t your fault? The only concern I see is you doing the repairs yourself instead of going through the dealership. Good luck!

@VIOLAHZ
I agree. I want to stand my ground and prioritize getting it fixed, but I really don’t want to pay for repairs if it’s just going to keep misfiring. I was hoping to keep this car for a few more years to drive back to Washington state.

@Dany
Her engine was under a full warranty. It took a year to get the replacement, but Hyundai covered the rental car the whole time.

There’s a service bulletin for replacing the affected ignition coil and a software update. I don’t understand why the dealer didn’t find this. TSB 20-FL-001H

Jacob said:
There’s a service bulletin for replacing the affected ignition coil and a software update. I don’t understand why the dealer didn’t find this. TSB 20-FL-001H

Can you share a link to more info? I’ve never heard of this before.

@Yvette
Here’s the link: https://static.nhtsa.gov/odi/tsbs/2020/MC-10172218-0001.pdf

Jacob said:
There’s a service bulletin for replacing the affected ignition coil and a software update. I don’t understand why the dealer didn’t find this. TSB 20-FL-001H

How is it that dealer technicians don’t know about these bulletins? I thought everything related to cars is computerized. It seems like the knowledge varies widely among dealerships, even though they all attend the same training.

@Callen
It’s often due to inexperience, laziness, oversight, or disinterest from the techs. There are many factors. People think all dealers are fully trained and have all the knowledge about Hyundai, but that’s not always the case. Each dealership has different levels of competence, which is often what people remember about dealers, leading to a bad reputation.

@Jacob
Thanks for confirming that. It makes sense.

Pull the spark plugs and check if they’re covered in oil. If they are, you might be dealing with the well-known oil consumption issue that many others have faced.

Amara said:
Pull the spark plugs and check if they’re covered in oil. If they are, you might be dealing with the well-known oil consumption issue that many others have faced.

I’ve heard a bit about that… do you know the remedy? Also, do most people get this covered under warranty?

@Dany
It depends on the mileage and if you bought it new or certified by Hyundai. They often replace engines for these issues. My wife purchased her 2017 Santa Fe from CarMax, but Hyundai wouldn’t cover it.

I faced similar issues with my 2017 Elantra SE around 60k miles. I took good care of that car too.

I would occasionally get a misfire in a cylinder. I replaced the spark plugs, and the shop I trust has some master mechanics, so my plugs were almost at the end of their lifespan anyway. When that didn’t solve the problem and it happened again, I replaced the coil. After that, I chased around two more coils, and when the last misfire happened, I had enough. I took a traveling job all over Arizona since I couldn’t risk being stranded.

I did some research and concluded that there’s likely no real fix for this, and it’s a serious warning sign that the engine may fail soon and will need replacement. My car was used, so I didn’t have the 100k warranty, but I ended up paying it off 2 years early and felt proud, thinking I had a reliable car for years to come. It’s unfortunate that these issues weren’t known when I bought it in 2018 because it’s a recognized problem with these Elantras. I fixed it and traded it in at 76k miles for a decent price. I still feel guilty about it because someone else will probably face the same issues.

I’m sorry you’re experiencing this too. I sometimes miss that car, even though my 2021 Kona Ultimate 1.6t AWD is much better in every aspect. It was my first car, and I never received any help with it, so it felt special.