NHTSA Complaint #11462505 — 2018 HYUNDAI ELANTRA

Engine would randomly idle mild to very rough when started and would sometimes correct and sometimes not correct while driving. This would turn on the check engine light for a misfire on cylinder 4. All ignition coils were replaced, and same code would happen. Hyundai was aware of this being a widespread issue and did a software update (Tech Bulletin 90C042R1). The problem continued, but seemed the check engine light would not come on as soon as before the software upgrade. Took back to dealership and they said the ignition coils would need to be Hyundai brand, change cylinder 4 to OEM and still having the issue. Engine also burns about 1 quart of oil every 7000 miles and often has a rough idle, with very rough idle periodically. I feel this would put myself and others on the road in danger if the engine were to fail while driving due to the ongoing damage rough idling appears to be causing to the engine.