AutoUtility currently tracks 56 official NHTSA owner defect complaints for the 2018 Mazda Mazda6. Engine & Cooling issues are the most frequently reported category, appearing in 30 complaints (53.6% of submitted records). Among these NHTSA complaint records, 1 filing cites a crash, 1 cites a fire, 1 reports one or more injuries.
Factual proportion of owner complaints categorized by automotive subsystem in NHTSA records
30 owner complaints submitted to NHTSA ODI for this subsystem.
9 owner complaints submitted to NHTSA ODI for this subsystem.
6 owner complaints submitted to NHTSA ODI for this subsystem.
4 owner complaints submitted to NHTSA ODI for this subsystem.
Specific mechanical, electrical, and driver-assist defect symptoms identified via deterministic narrative analysis
12 complaint narratives describe this symptom.
Representative defect filings submitted by owners to the NHTSA Office of Defects Investigation
"The car only has 70k miles on it. The engine started smoking under the hood. Immediately stopped to look. There was oil leaking but I could not see from where. I took it across the street to the Toyota dealership and had them look at it. They explained to me that there was a crack in the cylinder..."
"Got error message that said "Forward Smart City Brake Support Malfunction" slso fot "smart brake malfunction" while driving. The ac stopped, the car speedometer kept going from 50 to zero. The car died and couldn't open doors, windows. Lost steering while driving. We were able to get off road and..."
"Crack in Cylinder Head of engine. Mazda has been sued about this and have issued recalls on turbo engines, but not on non turbo ones though its the same systemic design issue with these engines. Wants me to pay 5-7k out of pocket."
"My cylinder head is leaking coolant. There is a well known and well documented issue with these cylinder heads cracking due to poor casting. This has become such a big issue that Mazda has even recalled the cylinder heads, BUT, only if the engine is equipped with Turbo. However, this issue is..."
"Car had a coolant leak due to cracked cylinder head that was defective from the factory it was fixed but now the car has engine problems again. Don’t want to keep having these issues in the future"
Reported defect complaint volume across sibling model years (2015–2021)
| Model Year | NHTSA Complaints | Crash Reports | Safety Recalls | Detailed Report |
|---|---|---|---|---|
| 2015 Mazda Mazda6 | 60 | 6 | 3 | View 2015 Problems → |
| 2016 Mazda Mazda6 | 76 | 9 | 1 | View 2016 Problems → |
| 2017 Mazda Mazda6 | 60 | 1 | 1 | View 2017 Problems → |
| 2018 Mazda Mazda6 Current Page | 56 | 1 | 2 | Current |
| 2019 Mazda Mazda6 | 6 | 0 | 1 | View 2019 Problems → |
| 2020 Mazda Mazda6 | 2 | 0 | 0 | View 2020 Problems → |
| 2021 Mazda Mazda6 | 17 | 0 | 0 | View 2021 Problems → |
Complete distribution of consumer defect reports across all 22 granular NHTSA system and subsystem classifications
| Vehicle Component / System | Total Complaints | Crash Reports | Fire Reports | Injury Entries | Fatality Entries |
|---|---|---|---|---|---|
| Engine NHTSA category: ENGINE | 22 | 0 | 0 | 0 | 0 |
| Other / Uncategorized NHTSA category: UNKNOWN OR OTHER | 4 | 0 | 0 | 0 | 0 |
| Fuel System NHTSA category: FUEL SYSTEM, GASOLINE | 3 | 0 | 0 | 0 | 0 |
| POWER TRAIN,ENGINE | 3 | 0 | 0 | 0 | 0 |
| Service Brakes NHTSA category: SERVICE BRAKES | 3 | 0 | 0 | 0 | 0 |
| Powertrain NHTSA category: POWER TRAIN | 2 | 0 | 0 | 0 | 0 |
| Structure & Body NHTSA category: STRUCTURE | 2 | 0 | 0 | 0 | 0 |
| UNKNOWN OR OTHER,ENGINE | 2 | 0 | 0 | 0 | 0 |
| Visibility & Wipers NHTSA category: VISIBILITY/WIPER | 2 | 0 | 0 | 0 | 0 |
| Back Over Prevention / Camera NHTSA category: BACK OVER PREVENTION | 1 | 0 | 0 | 0 | 0 |
| ELECTRICAL SYSTEM,ENGINE | 1 | 0 | 0 | 0 | 0 |
| ELECTRICAL SYSTEM,ENGINE,FUEL/PROPULSION SYSTEM | 1 | 0 | 0 | 0 | 0 |
| ELECTRICAL SYSTEM,UNKNOWN OR OTHER,ENGINE | 1 | 0 | 1 | 0 | 0 |
| Equipment & Accessories NHTSA category: EQUIPMENT | 1 | 0 | 0 | 0 | 0 |
| Fuel & Propulsion System NHTSA category: FUEL/PROPULSION SYSTEM | 1 | 0 | 0 | 0 | 0 |
| POWER TRAIN,ELECTRICAL SYSTEM | 1 | 0 | 0 | 0 | 0 |
| POWER TRAIN,UNKNOWN OR OTHER,ENGINE | 1 | 0 | 0 | 0 | 0 |
| Seat Belts NHTSA category: SEAT BELTS | 1 | 1 | 0 | 1 | 0 |
| STEERING,SUSPENSION,VEHICLE SPEED CONTROL | 1 | 0 | 0 | 0 | 0 |
| SUSPENSION,POWER TRAIN,SERVICE BRAKES | 1 | 0 | 0 | 0 | 0 |
| SUSPENSION,POWER TRAIN,WHEELS | 1 | 0 | 0 | 0 | 0 |
| UNKNOWN OR OTHER,ENGINE,FUEL/PROPULSION SYSTEM | 1 | 0 | 0 | 0 | 0 |
Cross-reference safety recalls, crash test safety ratings, and EPA fuel economy for this model year
Key performance indicators, EPA fuel economy specs, powertrain variants, and summary ratings.
Official recall campaigns, safety defect descriptions, and manufacturer free remedy instructions.
NHTSA 5-Star NCAP crash test results, driver assistance systems, and rollover resistance ratings.
EPA fuel economy ratings, electric range, and annual energy cost benchmarks.
Direct, deterministic answers synthesized from verified United States government databases for the 2018 Mazda Mazda6
In official NHTSA consumer records, the most frequently cited issue area for the 2018 Mazda Mazda6 is Engine & Cooling, appearing in 30 records (53.6% of submitted filings).
Secondary reported categories include Powertrain & Transmission (9) and Fuel & Propulsion System (6).
AutoUtility does not issue subjective reliability scores or commercial ratings. In official United States government records, NHTSA tracks 56 consumer defect complaints and 2 safety recall campaigns for the 2018 Mazda Mazda6.
Reviewing documented component complaint distributions, recall remedy notices, and active federal investigations provides an objective, evidence-based view of the vehicle's historical safety and defect record.
Among consumer complaint records on file with NHTSA for the 2018 Mazda Mazda6, 1 filing cites a crash, 1 cite smoke or fire, and 1 report one or more injuries.
Incident entries represent consumer descriptions at the time of submission to federal authorities and do not establish mechanical causation or legal liability.
The complaint records on this page are retrieved directly from the NHTSA Office of Defects Investigation (ODI) public database under 49 CFR Part 576.
Local Production Store Compiled: August 2026 • Deterministic Audited Dataset • Zero Dynamic External API Runtime Latency.