2018 Hyundai Sonata · symptom sheet
Engine knocking or ticking
- 32owner reports
- 19,500median miles
- $564median quote
- 1involved a crash
Newest report Jun 19, 2026 · checked Oct 2, 2026
32 of the 88 reports of engine failure on the 2018 Sonata describe engine knock.
Part of Engine failure, knocking or rod bearing (88 reports)
Tick what matches of 32 reports
Engine knock on other Sonata years
Report counts are for each model year on its own, so a newer car has had less time to collect them. Model years with too few reports of it for a sheet: 2019, 2020, 2021, 2022, 2023, 2024.
What got replaced
Owners who name the part that was replaced mention the knock sensor (18 reports), the engine (5 reports) and the rod bearing (5 reports).
Recalls and investigations
No recall on the engine covers the 2018 model year as of Oct 2, 2026.
NHTSA investigations into the engine on the Sonata
Loss of motive power. Closed dec 12, 2023.
Engine fires. Closed feb 5, 2024, led to recall 23V-877.
Scope and timeliness. Closed dec 22, 2021, led to recall 17V-226.
What owners paid
10 of the 32 reports quote a price. Each dot is one quote. The middle half runs $350 to $850.
When it happens
The middle half of failures fell between 3,000 and 107,000 miles, from the 20 reports that gave a mileage.
Is this a known problem?
The manufacturer has sent NHTSA 2 service bulletins or notices for the 2018 Hyundai Sonata that deal with this problem. Newest first.
Federal rules make a manufacturer send NHTSA a copy of any notice about a defect that goes to more than one dealer or owner. Most of these are service bulletins, the repair instructions manufacturers send to dealers. NHTSA generally leaves safety recall bulletins out of this file, and recalls are listed separately.
Hyundai is conducting a product improvement campaign to enhance the knock sensor software to detect abnormal engine bearing noise before potentially severe engine damage occurs.
Hyundai has developed a new engine monitoring technology called a Knock Sensor Detection System (KSDS). The technology uses software innovations and leverages existing engine sensors to continuously monitor for symptoms that may precede an engine failure.
What owners wrote
“Vehicle caught fire after repeatedly taking it to Hyundai for service . I complained about the oil consumption and knocking noises while the vehicle was still under warranty and it was denied.”
Filed Jun 19, 2026
Should you keep driving it?
This page can't tell you that. 1 of 32 reports involved a crash. Owners who file are the ones who had a bad experience, and nobody checks their reports. If the problem affects steering, braking, power or a fire risk, treat it as a safety fault and have it inspected before a long or high-speed drive.
File your own report with NHTSA. Complaint counts are how a problem gets an investigation. How reports land on this sheet.
Guide Taking it to a shop? How to describe this problem so it gets found
Other problems on this car
- Burns oil or oil level rises 75 reports
- Check engine light or misfire 66 reports
- Engine stalls or loses power while driving 53 reports