Check if it’s a coil issue. I have a 2017 Hyundai Elantra SE. I had a cylinder 1 misfire that got fixed under warranty with no problem. After hitting 70k miles, cylinder 3 misfired and I had the coil replaced outside of warranty. Both times, it was the coils. No issues since replacing the coil for cylinder 3. Currently at 121k miles.
In a very rare case, I had the same year with a cylinder 3 misfire caused by low fuel pressure. I’ve seen injectors fail too.
Is anyone else annoyed that the ‘d’ is not on the second line?
Had that happen to me as well. I switched it with engine coil 2 and got the same code for 2. From what I was told, it’s a pretty routine fix.
I went through the same thing with my recent purchase of a used 18 Elantra Sport. I replaced all the plugs and coils with OE ones and the code disappeared. I haven’t checked the MPG yet, but the check engine light has stayed off. It’s a simple job… all you need is a socket wrench, a 6" extension, and a 10 mm and 5/8" spark plug socket. It took me less than an hour for everything.
Did you replace the coil pack? That could also be the cause of what you’re seeing. Try swapping a coil pack from another cylinder and see if the misfire shifts to the new cylinder. If it does, congrats, you just fixed it!
It could be a spark plug, ignition coil, or injector. Plugs and coils are easy to swap between cylinders for testing. If the problem follows the swap, that’s your issue. If it doesn’t follow, you might have an injector issue or low compression. Low compression is not good news.
Replace the spark plugs and ignition coils. If it keeps misfiring, you probably have the rod bearing recall. You might be looking at rod knock, so take it to a Hyundai dealership to get the engine replaced. That’s what happened to me.
If you’ve replaced the spark plugs, it’s likely the coil.
They mention spark plugs and cylinders, but it’s really about how Hyundai engines burn oil improperly. There are a few band-aid fixes, but your car might be done for.